European Technical Approval No ETA-06/0006

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MEMBRE DE L'EOTA
MEMBER OF EOTA
European Technical Approval No ETA-06/0006
(English translation, the original version is in French)
Nom commercial :
Trade name :
Détenteur de l’ATE :
ETA Holder :
Type générique et utilisation prévue
du produit de construction :
Generic type and use of construction
product :
Valid from :
to :
Producteur du Procédé :
Kit Manufacturer :
Cet Agrément Technique Européen
contient :
This European Technical Approval
contains :
Procédé de précontrainte VSL
VSL Post-Tensioning System
VSL INTERNATIONAL Ltd.
Scheibenstrasse, 70
CH - 3014 BERNE
Procédés de précontrainte des structures par
post-tension
(communément appelés procédés de précontrainte)
Post-Tensioning Kits for Prestressing of Structures
(commonly called Post-Tensioning Systems)
31-07-2006
30-07-2011
CTT- Stronghold, SA
Ribera del Congost, s/n
SP - 08520 Les Franqueses del Vallès (Barcelona)
8+(4+40+28) pages incluant 3 annexes (0, 1, 2)
faisant partie intégrante du document.
8+(4+40+28) pages including 3 annexes (0, 1, 2)
which form an integral part of the document.
Organisation pour l’Agrément Technique Européen
European Organization for Technical Approvals

I - LEGAL BASIS AND GENERAL CONDITIONS
1- This European Technical Approval is issued by SETRA in accordance with:
- Council Directive 89/106/EEC of 21 December 1988 on the approximation of laws, regulations and
administrative provisions of Member States relating to construction products 1 , modified by Council
Directive 93/68/EEC 2 and Regulation (EC) N o 1882/2003 of the European Parliament and of the Council 3 ;
- Décret n°92-647 du 8 juillet 1992 4 concernant l'aptitude à l'usage des produits de construction
- Common Procedural Rules for Requesting, Preparing and the Granting of European Technical
Approvals set out in the Annex to Commission Decision 94/23/EC 5 ;
- ETAG 013, Edition June 2002, Post-Tensioning Kits for Prestressing of Structures.
2 - SETRA is authorized to check whether the provisions of this European Technical Approval are met.
Checking may take place in the manufacturing plant(s). Nevertheless, the responsibility for the conformity
of the products to the European Technical Approval and for their fitness for the intended use remains with
the holder of the European Technical Approval.
3 - This European Technical Approval is not to be transferred to manufacturers or agents of
manufacturers other than those indicated on page 0, or manufacturing plants other than those indicated
on page 0 of this European Technical Approval.
4 - This European Technical Approval may be withdrawn by SETRA, in particular pursuant to information
by the Commission according to Article 5 1 of Council Directive 89/106/EEC.
5 - Reproduction of this European Technical Approval including transmission by electronic means shall be
in full. However, partial reproduction can be made with the written consent of SETRA. In this case partial
reproduction has to be designated as such. Texts and drawings of advertising brochures shall not
contradict or misuse the European Technical Approval.
6 - The European Technical Approval is issued by the approval body in its official language(s). This
(These) version(s) corresponds (correspond) fully to the version circulated in EOTA. Translations into
other languages have to be designated as such.
1 o
Official Journal of the European Communities N L 40, 11.2.1989, p. 12
2 o
Official Journal of the European Communities N L 220, 30.8.1993, p. 1
3 o
Official Journal of the European Union N L 284, 30.10.2003, p. 1
4
JORF du 14 juillet 1992
5 o
Official Journal of the European Communities N L 17, 20.1.1994, p. 34
1

II - SPECIFIC CONDITIONS CONCERNING THE
EUROPEAN TECHNICAL APPROVAL
1 - Product definition and intended use
1.1 - Product definition
The VSL Post-Tensioning System consists, for convenience purposes, of two systems that rely upon a set
of common basic components: the VSL Multistrand System and the VSL Slab System.
According to this System, cables are considered to be primarily composed of ducts, tendons (using the
0.6" 'normal' or 'super' strand, i.e. Ø 15.2 or Ø 15.7, those defined in the White Draft pr EN 10138-3:
"Prestressing steels - Strands" or individually greased and sheathed monostrand complying with ETAG
013 Annex C.1), anchorages and/or couplers and other components such as protective products
necessary for ensuring either a permanent level of prestressing (during the entire reference life cycle) or a
temporary one (over a limited period) for civil engineering structural elements, buildings or any other type
of construction.
As long as EN 10138 does not exist 7-wire strands in accordance with national provisions shall be used.
The VSL Multistrand System (from 1 to 55 strand cables), defined in Annex 1 and intended more for
massive civil engineering parts, is used along with the strands specified above and the following
components:
- ducts:
- metallic: corrugated steel strip sheaths, steel tubes,
- made of plastic, the VSL PT-PLUS® ducting, polyethylene or polypropylene sheaths or tubes,
- anchorages:
- active or passive: type E (1 to 55 strands), type CS (7 to 37 strands),
- using bond: type H (1 to 37 strands),
- couplers: type K (3 to 37 strands);
- injection products:
- for rigid injection: with a cement base, in accordance with EN 447
- for flexible injection: with a grease base, with a wax base.
Filling materials covered by an ETA may also be employed.
The VSL Slab System (1 to 4 strands), defined in Annex 2 and primarily intended for thin construction
elements for building or bridge decks, is used along with the strands specified above and either bare
strands for the system with injection or individually greased and sheathed for the system without injection:
- ducts for the system with injection: the circular or flat corrugated steel strip sheaths, the circular or flat
VSL PT-PLUS® duct,
- anchorages:
- active or passive type S 6-1 (1 strand) and type S 6-4 (4 strands),
- embedded dead end type SF 6-1 (1 strand),
- using bond: type H for the system with injection applied to internal bonded tendons only,
- injection products for the system with injection: with a cement base, in accordance with EN 447.
Filling materials covered by an ETA may also be employed.
1.2 - Intended use
The VSL Post-Tensioning System has been designed to ensure the equilibrium of structures or of
sections of structures submitted to the gravity effects, live load effects, climatic effects or any other type
of action as well as to the imposed set of deformations.
The VSL Post-Tensioning System may be used for:
- new structural works,
- the repair and strengthening of existing structures.
2

The VSL Post-Tensioning System may also be employed in structures made of other materials than
concrete; this could entail structures made of concrete, masonry, steel, cast iron, wood or combinations
of several materials.
The tendons assembled as part of the VSL Post-Tensioning System may have the following basic use
categories:
- internal bonded tendon for concrete and composite structures,
- internal unbonded tendon for concrete and composite structures,
- external tendon for concrete structures with a tendon path situated outside the cross section of
the structure or member but inside its envelope.
(Cables for ground and rock anchors, external cables with a layout positioned beyond the structural
envelope or the structural component, and stay cables are not covered by the present ETA).
completed with the following optional use categories:
- restressable tendon (internal or external),
- exchangeable tendon (internal or external),
- internal bonded tendon with plastic duct,
- encapsulated tendon,
- electrically isolated tendon,
- tendon for use in structural steel or composite construction as external tendon,
- tendon for use in structural masonry construction as internal and/or external tendon,
- tendon for use in structural timber as internal and/or external tendon.
The tables presented in Chapters 1.4 and 3.4 of Annexes 1 and 2 establish the categories possible for
each of the approved anchorages.
1.3 Working life
The provisions, test and assessment methods in the ETAG 013 have been written based upon the
assumption that the estimated design working life (nominal design value of the intended life of a
structure) of the PT System is the same as the one specified in the Eurocodes relevant for the structure
in which it is intended to be used provided that the PT System is subject to appropriate use and
maintenance (see Chapter 7 of ETAG 013). Eurocode 1 specifies 100 years design working life for
bridges and other engineering structures. These provisions are based upon the current state of the art
and the available knowledge and experience.
The indication given on the design working life of a product cannot be interpreted as a guarantee given
by the producer (or the Approvals Body) but is regarded only as a means for choosing appropriate
components and materials in relation to the expected economically reasonable design working life of
structures for the works.
The relevant Eurocodes would be the following:
ENV 1990 "Eurocode 0": Basis of structural design
ENV 1991 "Eurocode 1": Actions on structures
ENV 1992 "Eurocode 2": Design of concrete structures
ENV 1993 "Eurocode 3": Design of steel structures
ENV 1994 "Eurocode 4": Design of composite steel and concrete structures
ENV 1995 "Eurocode 5": Design of timber structures
ENV 1996 "Eurocode 6": Design of masonry structures
2 - Product characteristics and verification methods
2.1 - Product characteristics
The components of the VSL Post-Tensioning System comply with the drawings and conditions described
in Annexes 1 and 2 of this European Technical Approval.
More detailed information related to confidential specifications (e.g.: materials, processing, surface,
dimensions, tolerances, manufacturing methods and control procedures) are included in the Technical
3

Evaluation dossier concerning this European Technical Approval, which has been deposited at the
Approval Body. This set of information is also to be sent, whenever necessary, to the Certification Body
responsible for Attestation of Conformity.
Essential requirements 1 (mechanical resistance and stability) and 3 (hygiene, health and the
environment) from Appendix I of the Construction Products Directive have been fulfilled. For the PT
System, the other requirements need not to be complied with.
Only product characteristics in relation to essential requirements 1 and 3 are to be verified. It should be
pointed out that, depending on their specific nature, some prestressed structures or parts of prestressed
structures may need to satisfy other requirements in respect to fire safety.
2.2 - Verification methods
Assessment of the fitness for use of the PT System with essential requirement 1 related to "mechanical
resistance and stability" was carried out, as stipulated in the European Technical Approval Guide focusing
on post-tensioning kits for prestressing of structures (ETAG 013).
The performances assessed in accordance with ETAG 013 allow to fulfill all relevant essential
requirements. Such performances deal for the most part with: resistance to static loads, effective load
transfer to the structure, and resistance to fatigue.
A set of specific tests were carried out as stated in ETAG 013 for the following optional use category:
electrical insulation applications.
The methods for verifying, evaluating and assessing suitability and test procedures comply with those
detailed in ETAG 013.
According to the kit manufacturer’s declaration, the post-tensioning kit does not contain any dangerous
substances.
In addition to the specific clauses relating to dangerous substances contained in this European Technical
Approval, there may be other requirements applicable to the products falling within its scope
(e.g. transposed European legislation and national laws, regulations and administrative provisions). In
order to meet the provisions of the EU Construction Products Directive, these requirements need also to
be complied with, when and where they apply.
This statement has been highlighted in Chapter 5 entitled "Injection and sealing" of both Annexes 1 and 2.
3 - Evaluation, Attestation of Conformity and CE marking
3.1 - The attestation of conformity system
The system of attestation of conformity specified by the European Commission in mandate 98/456/EC 6 is
the system 1+, with audit testing of samples, described in Council Directive (89/106/EEC) Annex III and is
detailed as follow:
3.1.1 - Tasks for the Kit Manufacturer (see Section 3.2.1):
1) Factory production control,
2) Further testing of samples taken at the factory by the manufacturer in accordance with a prescribed
test plan (see Annex 0);
3.1.2 - Tasks for the Certification Body (see Section 3.2.2):
1) Initial type testing of the product,
2) Initial inspection of factory and of factory production control (FPC),
3) Continuous surveillance, assessment and approval of factory production control (FPC)
4) Audit testing of samples.
3.2 - Responsibilities
3.2.1 - Tasks for the Kit Manufacturer
6 Official Journal of the European communities L201/112 of 3 July 1998
4

3.2.1.1 - General responsibilities of the Kit Manufacturer
The Kit Manufacturer shall keep available an updated list of all components manufacturers.
This list is to be provided to the Certification Body. Another copy may also be made available to the
Approval Body.
The Kit Manufacturer is responsible for the production and quality of components manufactured or ordered.
At least once a year, each components manufacturer has to be audited by the kit manufacturer. Each audit
report shall be made available to the Certification Body.
These audit reports include:
- Identification of the components manufacturer
- Date of audit of components manufacturer
- Summary of the results and records of the FPC since last audit
- Summary of the complaint records
- Evaluation of the components manufacturer concerning PPC
- Specific remarks as relevant
- Clear and unique statement whether the requirement of the ETA are met
- Name and position of signatory
- Date of signature
- Signature.
At least once a year specimens are taken by the kit manufacturer from at least one job site. One series of
single tensile element tests are performed according to Annex 0 (annex E3 of the ETAG 013) by the kit
manufacturer with these specimens. One series of single tensile element tests are performed with
components from only one site. The results of these test series are made available to the Certification Body.
These reports include:
- Identification of the job site where the components have been taken
- Date of sampling
- Identification of the components (e.g. anchor head, wedges, strand,…)
- Place and date of testing
- Summary of the results including a test report according to Annex E.3 of ETAG 013;
- Specific remarks as relevant
- Name and position of signatory
- Date of signature;
- Signature.
The kit manufacturer makes available for at least 10 years all records of relevant results concerning the
ETA and the audit reports concerning the components manufacturers.
3.2.1.2 - Factory Production Control (FPC)
3.2.1.2.1 - General
The kit manufacturer exercises permanent internal control of the production. All the elements, requirements
and provisions adopted by the kit manufacturer are documented in a systematic manner in the form of
written policies and procedures. This control system ensures that the PT System is in conformity with the
European Technical Approval.
The Factory Production Control is in accordance with the control plan of VSL named QM relating to the
European Technical Approval 06/0006 issued on 31-07-2006 which is part of the technical documentation
of this european technical approval. The control plan is laid down in the context of the factory production
control system operated by the manufacturer and deposited at SETRA.
The basic elements of the control plan comply with ETAG 013 annex E1. The results of the factory
production control shall be recorded and evaluated in accordance with the provisions of the control plan.
FPC and the prescribed test plan are according to Annex 0, which address the following aspects:
- manufacturing
- distribution and delivery to job site.
FPC system complying with EN ISO 9001 : 2000 and which addresses the requirements of the ETA is
recognized as satisfying the FPC requirements of the Directive.
5

Parts of the FPC may be transferred to an independent test laboratory. Nevertheless, the kit
manufacturer has the full responsibility for all results of the FPC.
3.2.1.2.2 - Control of the PT System components and materials
The characteristics of incoming materials which comply with a harmonized European technical
specification, having met the corresponding Attestation of Conformity procedure, are considered
satisfactory and need, except in case of justified doubt, no further checking. All materials are to be in
accordance with the requirements of the ETA and the corresponding specifications of the kit manufacturer.
Where harmonized technical specifications are not available, materials according to specifications valid in
the place of use may be used provided that their use is compatible with the results of approval tests.
Otherwise, the specifications are given in the ETA.
3.2.1.2.3 - Inspection and testing
The validity of the type and frequency of checks / testing conducted during production and on the final
product has to be considered as a function of the production process. This includes verification conducted
during production, on properties that cannot be inspected at a later stage and verification on the final
product. These include:
- Definition of the number of samples taken by the kit manufacturer
- Material properties e.g. tensile strength, hardness, surface finish, chemical composition,…
- Determination of the dimensions of components
- Check correct assembly
- Documentation of tests and test results.
All tests are performed according to written procedures with suitable calibrated measuring devices. All test
results are recorded in a consequent and systematic way.
The prescribed test plan relative to the PT System (see Annex 0) complies with stipulations in Annex E.1 of
ETAG 013, including the minimum test frequencies to perform.
3.2.1.2.4 - Control of non-conforming products
Products which are considered as not conforming with the ETA are immediately marked and separated from
such products which comply. The prescribed test plan addresses control of non-conforming products.
3.2.1.2.5 - Complaints
ETA Technical File includes provisions to keep records of all complaints about the PT System.
3.2.2 - Tasks of the Certification Body (CB)
The CB may act with its own resources or subcontract inspection tasks and testing tasks to inspection
bodies and testing laboratories.
3.2.2.1 - Initial type-testing
The results from tests performed during the approval procedure and then evaluated by the Approval Body
may be used by the Certification Body as initial type testing as required in the ETAG 013.
3.2.2.2 - Initial assessment of factory and factory production control
The Certification Body assesses both the factory capacities and the factory production control performed
by the kit manufacturer in order to ensure that, in compliance with the prescribed test plan, the
manufacturing resources and FPC are able to guarantee continuous and consistent manufacturing of PT
System components in accordance with ETA specifications.
3.2.2.3 – Continuous surveillance
The Certification Body shall perform surveillance inspections, Components Manufacturers inspections and
sample extractions either in the factories or on the job sites for the purpose of conducting independent
tests under its responsibility. Continuous surveillance and FPC evaluation are to proceed in accordance
with the prescribed test plan and in compliance with conditions laid out under the "Continuous
surveillance" heading found in the ETAG 013 guide and in Figure 8.1 in particular.
6

The kit manufacturer shall be inspected at least once a year. Its FCP will be checked and according to
Annex E.2, samples are taken for independent testing.
Each component manufacturer shall be inspected at least once during the period of validity of the ETA
that is at least once in five years.
The Certification Body shall provide SETRA, upon request, the results of certification and continuous
surveillance.
In cases of serious non conformities, related to important aspects of the performances of the posttensioning
system, which can not be corrected within the deadlines, the certification body shall withdraw
the certification of conformity and inform the SETRA without delay.
3.3 – CE-Marking
CE-marking is in accordance with the Construction Products Directive and the Guidance Paper
"D" named "CE marking under the construction products directive" (EC/OEAT 04/645 Document).
The delivery note, associated with the components of the PT System, shall contain the CE conformity
marking which consist of the CE-symbol and:
1. The name or identifying mark of the kit manufacturer
2. The last two digits of the year in which the marking was affixed
3. The number of the Certificate of Conformity
4. The ETA number
5 See information on ETA No number
6. The use category(ies)
7. The number of the Certification Body.
All other information is clearly separated from the CE-marking and the accompanying information.
4 - Assumptions under which the fitness for use of VSL PT System is favorably
assessed
4.1 - Production
This European Technical Approval document has been issued for the VSL PT System on the basis of
Manufacturer Technical Dossier submitted and verified by SETRA
Any anticipated changes to the process or in the production of components that may change the MTD
must be notified to SETRA, which would then decide whether change affects the ETA and, consequently,
the validity of the CE-marking and whether an additional assessment with modification of this ETA would
be necessary. Under all circumstances, SETRA consent is required prior to enacting the planned
modifications.
4.2 - Installation
The quality of a post-tensioned structure lies not only in its effective design, but also in the quality of its
execution. As regards post-tensioning, it goes without saying that the appropriate use of the PT System,
component quality and system installation quality serve to influence both suitability for the intended use
and the design working life
Basic information has been provided in Annexes 1 and 2 of ETA document. Although such information
proves essential for purposes of comprehending PT System application, it alone remains insufficient for
proceeding with the installation step. For this reason, the Post-Tensioning System has been set up for
installation to be performed by a PT Specialist Company.
Even though this field is submitted to the national regulatory conditions of EU Member States, it should be
recalled herein that the qualification of PT Specialist Companies encompasses their aptitude (specialized
equipment resources and certified staff) first to design the prestressed parts of structures and then to
7

prepare the corresponding set of components and work tasks, install the PT System (including cable
tensioning using appropriate devices) and performing the injection of protective filling material.
These last two tasks are to be carried out with equipment capable of meeting the requirements associated
with attaining precise measurements of certain physical magnitudes.
The tasks of design and installation may be extended, under some circumstances, by means of
monitoring and adjustment (whenever necessary) of the installed PT System.
5 - Indications
5.1 - Packaging, transportation and storage
Temporary protections, packaging, along with transportation and storage conditions for components of the
VSL PT System have been designed to ensure availability for worksite installation without any alteration of
their suitability for the particular intended use.
The detailed conditions to be adopted relative to the ducts, reinforcements, anchorages and protective
filling material have been set forth both in Chapter 7 of ETAG 013 and in the VSL Technical
Documentation (associated with the European Technical Approval).
5.2 - Installation
The entire set of equipment used for installing the PT System is submitted to periodic maintenance and
repair operations, whenever necessary.
Tensioning equipment measurement systems (pressure or force, displacement and/or movement) that get
included in the verification of magnitudes for the actions applied to structures undergo calibration in
compliance with: Chapter 7 of ETAG 013, the national provisions, and the set of practices prescribed in
the VSL Technical Documentation (associated with the European Technical Approval).
8

Annex 0 of the European Technical Approval No. ETA-06/0006 1
Annex 0
ETA APPLICATION
1 - Commitments assumed by the ETA Holder
Once installed, the VSL Post-Tensioning System makes a vital contribution both to the permanent
equilibrium of structures and to their durability.
In light of the terms inherent in this European Technical Approval (ETA), which serve to certify the
fitness for use of the PT System, its service capabilities and its working life as well as to prescribe the
resources utilized by the companies involved (see Appendix D of ETAG 013), it is essential for each
of the prerequisite measures to be applied during the fabrication and installation steps that
accompany the design step in promoting proper use of the PT System.
In this aim, the ETA Holder agrees to apply and ensure application of this approval by the Kit
Manufacturer, the Component Manufacturers and the PT Specialist Companies such that the installed
PT System proves capable of satisfying the designated set of basic requirements (in compliance with
Construction Products Directive, Chapter 1, Article 2.1).
2 - Responsibility of both the ETA Holder and Kit Manufacturer
The components of the VSL Post-Tensioning System are produced in accordance with the conditions
of the present European Technical Approval by the Kit Manufacturer and selected Component
Manufacturers, using the production resources indicated and identified during inspections and on site
audits performed by both the Approval and Certification Bodies.
The Kit Manufacturer guarantees that all components of the PT System and relative individual
components for which the ETA has been issued comply with the specifications given in the ETA. For the
most important components, the following table summarizes the minimum procedures which have to be
performed.

Annex 0 of the European Technical Approval No. ETA-06/0006 2
"Prescribed test plan"
1 2 3 4 5 6
Component Item Test / Check Traceability 4 Minimum
frequency
Anchorage zone components
Material 7
Anchor plate
Anchor head,
Coupler
Wedges,
Compression
fitting
Detailed
dimensions 5
Visual inspection 3 Check
Material 7
Detailed
dimensions 5
Visual inspection 3 Check
Material 7
Treatment,
hardness
Detailed
dimensions 5
Visual inspection 3 Check
Documen-
tation
Check 100% "2.2" 1,6
bulk 6
Test 3%
≥ 2 elements
Yes
100% No
Check 100% "3.1.B" 1
full
Test 5%
≥ 2 elements
Yes
100% No
Check 100% "3.1.B" 1
full
Test 0.5%
≥ 2 elements
Yes
Test 5%
≥ 2 elements
Yes
100% No
Current zone components
Check "CE" 2
100% "CE" 2
Duct Material 7
Visual inspection 3 Check 100% No
Strand Material 7
Check 100 % "CE" 2
Diameter
Visual inspection
Test Each coil No
3 National
Check
Certification
till "CE" 2
Each coil No
Cement 7
Check full 100% "CE" 2
Constituents
of filling
material as
per EN 447
Admixtures,
additions, ... 7
Check bulk 100% "CE" 2
Monostrand Material 7
Check National
Certification
till "CE" 2
100% "CE" 8
Plastic pipes Material 7
Check full 100% "CE" 2
Plastic ducts Material 7
Check full 100% "CE" 8
All samples are to be extracted at random and clearly identified.
Details on sampling procedures including methods of recording as well as test methods have been
agreed between the Approval Body and the Kit Manufacturer as part of the prescribed test plan.
Preferably standardized sampling and test methods are used. Generally all results are reported in the
test reports in such a way to enable direct comparison with the specification’s data in the ETA or
subsidiary documentation.
1
"2.2": Test report type "2.2" according to EN 10 204 (this applies to simple steel
anchor plates only).
2 "3.1.B": Inspection certificate type "3.1.B" according to EN 10 204.
If the basis of "CE"-marking is not available, the prescribed test plan has to include appropriate
measures, only for the time until the harmonized technical specification is available.

Annex 0 of the European Technical Approval No. ETA-06/0006 3
3 Visual inspections means e.g.: main dimensions, gauge testing, correct marking or
labelling, appropriate performance acceptability, surface fins, kinks, smoothness, corrosion, coating,
etc., as given in the prescribed test plan.
4 full: Full traceability of each component to its raw material.
bulk: Traceability of each delivery of components to a defined point.
5 Detailed dimensions mean measuring of all dimensions and angles according to the
specifications as given in the prescribed test plan.
6 Only if the force transfer unit is a "simple plate". Otherwise appropriate procedures
have to be introduced.
7 Material checks are included for information only as these are not part of the
prescribed test plan.
8 If the basis of "CE"-marking is not available, the prescribed test plan has to include
appropriate measures. The certificate shall be based on specific testing on the fabrication lot from which
the supply has been produced, to confirm specified properties, and shall be prepared by a department
of the supplier which is independent of the production department.
Note: Generally speaking, all tests, inspections, etc. are aimed at verifying that the information
contained in manufacturing drawings as well as in the ultimate set of associated specifications has
actually been applied to the components.
During surveillance inspections, the Certification Body has to take samples of components of the PT
System or the relative individual components for which the ETA has been granted for independent
testing. For the most important components, the table given below summarises the minimum
procedures which are performed by the Certification Body.
"Audit testing"
1 2 3 4
Component Item Test / Check Sampling Number of
components per visit
Anchor head, Coupler Material according to specification Check, test
1
Wedges,
Compression fitting
Single tensile
element test
Detailed dimensions Test
Visual inspection 9 Check
Material according to specification Check, test 2
Treatment Test 2
Detailed dimensions Test 1
Main dimensions, surface hardness Test 5
Visual inspection 9 Check 5
Single tensile element test
according to Annex E.3
Test 1 series
All samples are to be randomly selected and clearly identified.
Details on sampling procedures including methods of recording as well as test methods have been
agreed between the Approval Body and the Kit Manufacturer as part of the prescribed test plan.
Preferably standardised sampling and test methods are used. Generally all results are reported in the
test reports in such a way to enable direct comparison with the specification’s data in the ETA or
subsidiary documentation.

Annex 0 of the European Technical Approval No. ETA-06/0006 4
9 Visual inspections means e.g. : main dimensions, gauge testing, correct marking or labelling,
appropriate performance, surface, fins, kinks, smoothness, corrosion, coating, etc.
10 Applied to special grout covered by an ETA specified within the PT system.
3 - Responsibility assigned the ETA Holder and PT Specialist Companies
The respective tasks and responsibilities of the ETA Holder and PT Specialist Companies are
expressed in Appendix D of ETAG 013.
Installation of the VSL Post-Tensioning System is carried out in full compliance with the present
European Technical Approval, all related European level documents, and all pertinent National
application documents at the Country level.

Annex 1
TECHNICAL DATA
OF THE
VSL MULTISTRAND SYSTEM

Annex 1 of the European Technical Approval No ETA-06/0006 2
TABLE OF CONTENTS
Title Page
1. DEFINITION OF THE SYSTEM
1.1 PRINCIPLE OF THE VSL MULTISTRAND SYSTEM 4
1.2 CHARACTERISTICS OF SYSTEM UNITS 5
1.3 ANCHORAGES 6
1.3.1 PRESENTATION OF THE ANCHORAGES
1.3.2 LIST OF APPROVED ANCHORAGES
1.4 CATEGORIES OF USE, POSSIBILITIES AND OPTIONS 7
1.4.1 USES AND OPTIONS OF THE VSL MULTISTRAND SYSTEM
1.4.2 POSSIBILITIES OF THE VSL MULTISTRAND SYSTEM
2. STRANDS AND DUCTS
2.1 STRANDS USED 9
2.2 DUCTING 9
2.2.1 TYPES AND DIMENSIONS OF USABLE DUCTS
2.2.2 METAL DUCTS
2.2.3 PLASTIC DUCTS
2.2.4 ACCESSORIES FOR INLETS, BLEED VENTS AND OUTLETS
2.2.5 CONNECTION WITH TRUMPETS
2.3 CABLE LAYOUT 11
2.3.1 STRAIGHT LENGTHS BEHIND THE ANCHORAGES
2.3.2 RADIUS OF CURVATURE
2.3.3 SPACING OF SUPPORTS AND TOLERANCES
2.3.4 STRAND CUT LENGTH
2.4 INSTALLATION OF DUCTS AND STRANDS 12
2.5 PROVISIONAL PROTECTION AND LUBRICATION 13
2.6 CALCULATION ELEMENTS 13
2.6.1 FRICTION LOSSES
2.6.2 BASIS FOR EVALUATING ELONGATIONS
2.6.3 SETTING OF ANCHORAGE WEDGES
3. ANCHORAGES
3.1 DESCRIPTION OF ANCHORAGE COMPONENTS 15
3.1.1 LIVE END / DEAD END ANCHORAGES
3.1.2 COUPLERS
3.1.3 PRESENTATION AND PACKING OF ANCHORAGES
3.2 ORGANIZATION OF SUPPLY QUALITY 16
3.3 IMPLEMENTATION OF VARIOUS ANCHORAGES 16
3.3.1 TYPE "E" AND "CS" LIVE END ANCHORAGES
3.3.2 TYPE "E" AND "CS" DEAD END ANCHORAGES
3.3.3 TYPE "H" BOND ANCHORAGES
3.3.4 TYPE "K" COUPLER
3.4 ANCHORAGE ARRANGEMENTS 18
3.5 GEOMETRICAL AND MECHANICAL USE CONDITIONS 18
3.5.1 CLEARANCE BEHIND ANCHORAGES
3.5.2 CONCRETE COVER AND ANCHORAGE SPACING
3.6 BURSTING REINFORCEMENT 20
4. STRESSING
4.1 STRESSING EQUIPMENT 21
4.1.1 STRESSING JACKS
4.1.2 HYDRAULIC PUMPS
4.1.3 MEASUREMENT INSTRUMENTS AND SYSTEMS
4.2 PROCESSES OF STRESSING AND CONTROL PROCEDURE 22
4.2.1 FORCE MEASUREMENTS

Annex 1 of the European Technical Approval No ETA-06/0006 3
4.2.2 ELONGATION MEASUREMENTS
5. INJECTION AND SEALING
5.1 GENERAL INFORMATION 23
5.2 INJECTION PRODUCTS 23
5.2.1 PRODUCT FOR BONDED CABLES
5.2.2 PRODUCT FOR UNBONDED CABLES
5.3 INJECTION EQUIPMENT 24
5.4 INJECTION AND CONTROL PROCEDURE 24
5.5 SEALING 24
6. SCHEMATIC DRAWINGS 25

Annex 1 of the European Technical Approval No ETA-06/0006 4
CHAPTER 1
1. SYSTEM DEFINITION
DEFINITION OF THE SYSTEM
1.1 PRINCIPLE OF THE VSL MULTISTRAND SYSTEM
The cable or unit of the VSL Multistrand System is composed of a bundle of strands made of high-strength steel
called a "tendon", along with the associated set of anchorages.
The tendon has to be encased within a duct such as a sheath or tube, etc. The void thereby produced can
potentially be filled with an injected material for the purpose of bonding with the structure and/or inhibiting
corrosion.
The constituting strands are those defined in the European Standard White Draft pr EN 10138-3: "Prestressing
steels - Strand". They refer to 7-wire strands with nominal diameters of ∅ 15.2 and 15.7 mm (fpk = 1 860 N/mm 2
or fpk = 1 770 N/mm 2 ).
As long as EN 10138 does not exist, 7-wire strands in accordance with national provisions shall be used.
The VSL Multistrand system is able to accommodate bare strands and individually sheathed and greased
(protected) monostrands.
By varying both the strand diameter and number (and, if applicable, their specified characteristic value of
maximum force), it would be possible to obtain a value for the characteristic tensile strength per cable or unit
that varies between 260 and 15 345 kN.
All strands of a cable are simultaneously stressed, yet each one is individually locked within a conical anchoring
hole by means of wedges.
The anchorage function is performed by clamping during strand moving back at the time of pressure release in
the jack.
The choice of post-tensioning units, as dictated by force requirements, leads for a given strand diameter and
characteristic strength to a specific number of strands to be placed. In conjunction with this design element, the
choice of type of anchorage associated with the cable depends on the intended function and application of the
particular unit.
The designation of post-tensioning units is expressed with reference to both the type and number of component
strands. The VSL commercial labeling is explained below:
The labeling of units 6-1… 6-55 or 6S-1… 6S-55 signifies:
the first digit indicates strand diameter,
6 = ∅ 6 × 1/10" = T15.2 ∅15.2 mm
6S = ∅ 6 × 1/10" S = T15.7 ∅15.7 mm (S stands for super).
the subsequent digits indicate the number of strands composing the unit.
To provide greater detail, the designation of units begins with the names of the anchorages placed at the ends.
The following designation serves as an example:
Cable VSL E-E 6S-12 L = 50.000 (1)
The functions and names of the anchorages will be defined hereafter. The cable features a length of 50.000 m
and has been stressed at one (1) end.
To cover the entire range from 1 to 55 strands, an array of basic anchorages has been developed, i.e.: 1 - 2 - 3 -
4 - 7 - 12 - 15 - 19 - 22 - 27 - 31 - 37 - 43 - 55, thus enabling the creation of any intermediate unit, considering
that the number of strands placed may be less than the number of conical holes of the anchorage.
In incompletely filled anchor heads, the present strands have to be arranged to centre the applied load to the
anchor head.

Annex 1 of the European Technical Approval No ETA-06/0006 5
1.2 CHARACTERISTICS OF SYSTEM UNITS
On the basis of the strand characteristics defined in draft Standard "pr EN 10138-3: Prestressing steels - Part 3:
Strand", the values of tendon cross-sections Ap, maximum forces under anchorage upon tensioning recom-
mended by EC2 : Pmax = min {k1.Ap.fpk; k2.Ap.fp0.1k}, with k1 = 0.8, k2 = 0.9, fpk = 1 860 N/mm 2 , fp0.1k = 0.88 fpk, of
VSL post-tensioning units are as follows :
Number of
strands in the
prestressing
unit
Ap
STRAND ∅ 15.2 - T15.2 or 6
fpk = 1 860 N/mm 2
Fpk = 260 kN Fp0.1k = 229 kN
Ap.fpk
0.8
Ap.fpk
Ap.fp0.1k
0.9
Ap.fp0.1k
Ap
STRAND ∅ 15.7 - T15.7 or 6S
fpk = 1 860 N/mm 2
Fpk = 279 kN Fp0.1k = 246 kN
Ap.fpk
0.8
Ap.fpk
Ap.fp0.1k
0.9
Ap.fp0.1k
mm² kN kN kN kN mm² kN kN kN kN
1 140 260.0 208.0 229.0 206.1 150 279.0 223.2 246.0 221.4
2 280 520.0 416.0 458.0 412.2 300 558.0 446.4 492.0 442.8
3 420 780.0 624.0 687.0 618.3 450 837.0 669.6 738.0 664.2
4 560 1 040.0 832.0 916.0 824.4 600 1 116.0 892.8 984.0 885.6
5 700 1 300.0 1 040.0 1 145.0 1 030.5 750 1 395.0 1 116.0 1 230.0 1 107.0
6 840 1 560.0 1 248.0 1 374.0 1 236.6 900 1 674.0 1 339.2 1 476.0 1 328.4
7 980 1 820.0 1 456.0 1 603.0 1 442.7 1 050 1 953.0 1 562.4 1 722.0 1 549.8
8 1 120 2 080.0 1 664.0 1 832.0 1 648.8 1 200 2 232.0 1 785.6 1 968.0 1 771.2
9 1 260 2 340.0 1 872.0 2 061.0 1 854.9 1 350 2 511.0 2 008.8 2 214.0 1 992.6
10 1 400 2 600.0 2 080.0 2 290.0 2 061.0 1 500 2 790.0 2 232.0 2 460.0 2 214.0
11 1 540 2 860.0 2 288.0 2 519.0 2 267.1 1 650 3 069.0 2 455.2 2 706.0 2 435.4
12 1 680 3 120.0 2 496.0 2 748.0 2 473.2 1 800 3 348.0 2 678.4 2 952.0 2 656.8
13 1 820 3 380.0 2 704.0 2 977.0 2 679.3 1 950 3 627.0 2 901.6 3 198.0 2 878.2
14 1 960 3 640.0 2 912.0 3 206.0 2 885.4 2 100 3 906.0 3 124.8 3 444.0 3 099.6
15 2 100 3 900.0 3 120.0 3 435.0 3 091.5 2 250 4 185.0 3 348.0 3 690.0 3 321.0
16 2 240 4 160.0 3 328.0 3 664.0 3 297.6 2 400 4 464.0 3 571.2 3 936.0 3 542.4
17 2 380 4 420.0 3 536.0 3 893.0 3 503.7 2 550 4 743.0 3 794.4 4 182.0 3 763.8
18 2 520 4 680.0 3 744.0 4 122.0 3 709.8 2 700 5 022.0 4 017.6 4 428.0 3 985.2
19 2 660 4 940.0 3 952.0 4 351.0 3 915.9 2 850 5 301.0 4 240.8 4 674.0 4 206.6
20 2 800 5 200.0 4 160.0 4 580.0 4 122.0 3 000 5 580.0 4 464.0 4 920.0 4 428.0
21 2 940 5 460.0 4 368.0 4 809.0 4 328.1 3 150 5 859.0 4 687.2 5 166.0 4 649.4
22 3 080 5 720.0 4 576.0 5 038.0 4 534.2 3 300 6 138.0 4 910.4 5 412.0 4 870.8
23 3 220 5 980.0 4 784.0 5 267.0 4 740.3 3 450 6 417.0 5 133.6 5 658.0 5 092.2
24 3 360 6 240.0 4 992.0 5 496.0 4 946.4 3 600 6 696.0 5 356.8 5 904.0 5 313.6
25 3 500 6 500.0 5 200.0 5 725.0 5 152.5 3 750 6 975.0 5 580.0 6 150.0 5 535.0
26 3 640 6 760.0 5 408.0 5 954.0 5 358.6 3 900 7 254.0 5 803.2 6 396.0 5 756.4
27 3 780 7 020.0 5 616.0 6 183.0 5 564.7 4 050 7 533.0 6 026.4 6 642.0 5 977.8
28 3 920 7 280.0 5 824.0 6 412.0 5 770.8 4 200 7 812.0 6 249.6 6 888.0 6 199.2
29 4 060 7 540.0 6 032.0 6 641.0 5 976.9 4 350 8 091.0 6 472.8 7 134.0 6 420.6
30 4 200 7 800.0 6 240.0 6 870.0 6 183.0 4 500 8 370.0 6 696.0 7 380.0 6 642.0
31 4 340 8 060.0 6 448.0 7 099.0 6 389.1 4 650 8 649.0 6 919.2 7 626.0 6 863.4
32 4 480 8 320.0 6 656.0 7 328.0 6 595.2 4 800 8 928.0 7 142.4 7 872.0 7 084.8
33 4 620 8 580.0 6 864.0 7 557.0 6 801.3 4 950 9 207.0 7 365.6 8 118.0 7 306.2
34 4 760 8 840.0 7 072.0 7 786.0 7 007.4 5 100 9 486.0 7 588.8 8 364.0 7 527.6
35 4 900 9 100.0 7 280.0 8 015.0 7 213.5 5 250 9 765.0 7 812.0 8 610.0 7 749.0
36 5 040 9 360.0 7 488.0 8 244.0 7 419.6 5 400 10 044.0 8 035.2 8 856.0 7 970.4
37 5 180 9 620.0 7 696.0 8 473.0 7 625.7 5 550 10 323.0 8 258.4 9 102.0 8 191.8
38 5 320 9 880.0 7 904.0 8 702.0 7 831.8 5 700 10 602.0 8 481.6 9 348.0 8 413.2
39 5 460 10 140.0 8 112.0 8 931.0 8 037.9 5 850 10 881.0 8 704.8 9 594.0 8 634.6
40 5 600 10 400.0 8 320.0 9 160.0 8 244.0 6 000 11 160.0 8 928.0 9 840.0 8 856.0
41 5 740 10 660.0 8 528.0 9 389.0 8 450.1 6 150 11 439.0 9 151.2 10 086.0 9 077.4
42 5 880 10 920.0 8 736.0 9 618.0 8 656.2 6 300 11 718.0 9 374.4 10 332.0 9 298.8
43 6 020 11 180.0 8 944.0 9 847.0 8 862.3 6 450 11 997.0 9 597.6 10 578.0 9 520.2
44 6 160 11 440.0 9 152.0 10 076.0 9 068.4 6 600 12 276.0 9 820.8 10 824.0 9 741.6
45 6 300 11 700.0 9 360.0 10 305.0 9 274.5 6 750 12 555.0 10 044.0 11 070.0 9 963.0
46 6 440 11 960.0 9 568.0 10 534.0 9 480.6 6 900 12 834.0 10 267.2 11 316.0 10 184.4
47 6 580 12 220.0 9 776.0 10 763.0 9 686.7 7 050 13 113.0 10 490.4 11 562.0 10 405.8
48 6 720 12 480.0 9 984.0 10 992.0 9 892.8 7 200 13 392.0 10 713.6 11 808.0 10 627.2
49 6 860 12 740.0 10 192.0 11 221.0 10 098.9 7 350 13 671.0 10 936.8 12 054.0 10 848.6
50 7 000 13 000.0 10 400.0 11 450.0 10 305.0 7 500 13 950.0 11 160.0 12 300.0 11 070.0
51 7 140 13 260.0 10 608.0 11 679.0 10 511.1 7 650 14 229.0 11 383.2 12 546.0 11 291.4
52 7 280 13 520.0 10 816.0 11 908.0 10 717.2 7 800 14 508.0 11 606.4 12 792.0 11 512.8
53 7 420 13 780.0 11 024.0 12 137.0 10 923.3 7 950 14 787.0 11 829.6 13 038.0 11 734.2
54 7 560 14 040.0 11 232.0 12 366.0 11 129.4 8 100 15 066.0 12 052.8 13 284.0 11 955.6
55 7 700 14 300.0 11 440.0 12 595.0 11 335.5 8 250 15 345.0 12 276.0 13 530.0 12 177.0
Note : prestressing force applied to structure must be in accordance with national regulations.

Annex 1 of the European Technical Approval No ETA-06/0006 6
The system can obviously be used with strands displaying a specific characteristic tensile strength of less than
that proposed in the table as strands with fpk = 1 770 N/mm 2 . The provisions for tendons with strands with a
characteristic tensile strength fpk = 1 860 N/mm 2 also apply to tendons with strands with fpk < 1 860 N/mm 2 .
The draft Standard pr EN 10138-3 sets the following criteria for the other useful characteristics of prestressing
strands composing the VSL units:
- Elongation at maximal force: ≥ 3.5%
- Relaxation at 0.70 fpk after 1,000 hours: ≤ 2.5%
- Relaxation at 0.80 fpk after 1,000 hours: ≤ 4.5%
- Fatigue behavior (0.70 fpk; 190 N/mm 2 ): ≥ 2x10 6 cycles
- Maximum D value of deflected tensile test: ≤ 28%
- Modulus of elasticity Ep: 195 000 N/mm 2
Even though the modulus of elasticity of both the tendon or bundle of strands and the (single) strand are
somewhat different, VSL still recommends adopting, for the cable calculations, the measured strand value that
had been transmitted upon delivery of the supply of strands.
Individually greased and sheathed monostrands have the same mechanical properties as listed above for bare
strands.
1.3.1 PRESENTATION OF THE ANCHORAGES
1.3 ANCHORAGES
The VSL Multistrand System anchorages may, depending on their function and commercial labeling, be
classified as one of the following:
Type "E" and "CS" live end anchorages
These active anchorages are designed to anchor the tendons at the end through which stressing of the entire
set of bundled strands will be carried out.
They are composed of an anchor head (cylindrical for the anchorage E or a hexagonal-base prism for the "CS"
anchorage) drilled with the same number of conically-shaped holes as strands to be anchored; the anchoring
step is performed at each strand using wedges to provide a strong grip.
The anchor head is supported by the concrete via an "E" or "CS" type anchor plate connected to an "E" or "CS"
type trumpet housing deviating the strands to the current duct.
Type "E" and "CS" dead end anchorages
These passive anchorages serve to block the tendons at the end on which no stressing force is to be exerted.
This category only includes those anchorages that remain accessible at the time of stressing.
Type "E" or "CS" anchorages, which feature pre-clamped wedges and which may be controlled during stressing,
are used for this purpose.
Type "H" bonded anchorages
These dead end anchorages rely, at least in part, on bond in order to maintain the tendon extremity fastened
with respect to the concrete.
In type "H" anchorages, the clean strands exhibit wires, over a given bond length, folded at their extremities to
form an onion.
Type "K" couplers
These anchorages ensure the continuity of two tendons placed in tension one after the other when two distinct
phases of the construction job overlap.
Within "K" type couplers, the first-phase cable is anchored on the coupler side with a type "E" or "CS" anchor
(transfer) plate whose head labeled "K" contains the housing units for the coupling around its periphery.
The second-phase cable, on the coupler side, is anchored by means of compression fittings on the strands
placed into the aforementioned housings.
The two coupled tendons must be units of the same number of strands and the force in the second phase cable
shall not be larger than the force in the first phase cable.
The coupling is then insulated from the concrete by means of a sleeve.

Annex 1 of the European Technical Approval No ETA-06/0006 7
1.3.2 LIST OF APPROVED ANCHORAGES
The set of approved anchorages that allow creating all sorts of intermediate prestressing units have been
categorized in the following table:
CABLE
ANCHORAGE
Function Live End Dead End Bond Coupler
Unit Commercial label E CS E CS H K
1T15.2 / 1T15.7 6-1 / 6S-1
2 2
3 3
4 4
7 7
12 12
15 15
19 19
22 22
27 27
31 31
37 37
43 43
55 55
The stressing of tendons at PT system anchorages is only conducted by VSL stressing jacks, which are
presented in Chapter 4.
1.4 CATEGORIES OF USE, POSSIBILITIES AND OPTIONS
1.4.1 USES AND OPTIONS OF THE VSL MULTISTRAND SYSTEM
VSL Multistrand System units may be:
- internal or external (to the concrete or to one another material),
- with or without a bonded or unbonded permanent injection, and
- applied in structures composed indiscriminately of various construction materials.
These units may entail:
- an adjustable force, and/or
- the potential for replacement provided the absence of bonding with the structure.
They can also be conceived for applications that are:
- encapsulated (leak-tight, waterproof), and
- electrically isolated (electrical isolation implies a strong waterproofing).
Uses of units of VSL Multistrand System made of approved anchorages
Uses Anchorages E CS H K
internal* bonded cable with metallic duct
internal* bonded cable with plastic duct
internal* unbonded
external* bonded cable
external* unbonded cable
tendon for use in various material as external cable
restressable tendon
exchangeable tendon
encapsulated tendon (leak tight)
electrically isolated tendon
(*) of concrete

Annex 1 of the European Technical Approval No ETA-06/0006 8
As noted before,
- absence of bonding with the structure for exchangeable cable means soft injection or double pipe at
anchorage and deviator in case of rigid injection. The clearance between outside diameter of tendon duct and
inside diameter of formwork pipe in structure has to be 10 mm minimum.
- the VSL Multistrand System may be introduced without grouting, which for example is the case when
tendons are left without protection due to their provisional use, or their location within a neutral environment.
It goes without saying that all these potential uses and options presume the availability of adequate choices and
combinations of all cable components as indicated in this ETA:
- for strands see Chapter 2.1 "Strands used",
- for ducts see Chapter 2.2 "Ducting",
- for anchorages see Chapter 3.4 "Anchorage arrangements",
- for injection see Chapter 5.2 "Injection products".
1.4.2 POSSIBILITIES OF THE VSL MULTISTRAND SYSTEM
The VSL Multistrand System is able to take advantage of the following unique set of possibilities:
- Partial stressing or stressing in stages:
When prestressing needs to be applied gradually, the stressing may be performed in stages. As the first
partial stressing step gets carried out, at the beginning of the second stage, the wedges are unclamped by
action of the jack on the cable. Once the targeted force has been reached, pressure in the jack is relaxed
and the wedges are once again clamped inside the anchor head. This procedure consists of the same
steps as for tensioning of a long cable whose elongation necessitates several successive jack strokes.
- Overstressing with shimming:
Upon loading of the anchorage during relaxing the jack pressure, due to wedges draw in, a simultaneous
setting of the strands takes place causing a reduction of elongation and a drop in tension at the cable end.
It is still possible however to adjust tension to the desired value by use of a jack chair ring that enables
pressing the jack no longer upon the anchor head but rather via jack chair upon the bearing plate. In this
case, since the stressing had been conducted under typical conditions and the wedges locked definitively,
tensioning is resumed by bringing the head back to the target displacement (the wedge draw in or other
value), and then shimming between the anchor head and the anchor plate with split shim (see chapter
2.6.3) .
- Destressing procedure:
The destressing of an anchored cable by a type "E" or "CS" anchor head is possible using a special tooling
assembly mounted on the tensioning jack provided that (1) the required strand overlengths have been
conserved, (2) that the tendon remains unbonded to the structure.
From the aforementioned, two zones would appear to stand out, the current zone and the anchorage zone; they
will be presented in greater detail within the following chapters entitled "Strands and ducts" and "Anchorages".

Annex 1 of the European Technical Approval No ETA-06/0006 9
CHAPTER 2
STRANDS 2. TENDONS AND DUCTS DUCTS
2.1 STRANDS USED
The high-strength prestressing steel (strands) composing the tendons are labeled "Y1860S7 – No. 1.1366" and
are defined in the draft Standard "pr EN 10138-3: Prestressing steels – Part 3: Strand". Alternatively, the
strands labeled "Y1770S7 – No. 1.1365" may also be employed.
The primary characteristics have been recalled in Section 1.2.
Monostrands (individually greased and sheathed) can be used for unbonded tendons, either internal or external
to concrete or other materials. They are compliant with Annex C.1 of the ETAG 013, which specifies the
requirements, verification methods and acceptance criteria of both the grease and the sheathing.
2.2 DUCTING
The VSL Multistrand System can use several types of duct as provided in this section. Duct type selection
depends on the specific project, the final use designed for the structure and the options selected for the posttensioning
units.
2.2.1 TYPES AND DIMENSIONS OF THE USABLE DUCTS
Depending on the specific application, various types of ducts may be employed. From a general standpoint, the
ducts used must be mechanically resistant, display continuity in shape, ensure continuity of the seal and,
ultimately, continuity in electrical insulation over their entire length, as well as comply with the project's bond
requirements while not causing any chemical attack to the prestressing steel.
Without claiming to be exhaustive, the following table of frequently-used ducts can be cited as having
demonstrated their capacities in the uses and applications associated with the given options:
Applications
Ducts
Corrugated metal
duct
Metal Ducts Plastic Ducts
Smooth metal duct
VSL PT-PLUS ®
Duct
Smooth plastic duct
polyethylene,
polypropylene
Internal with
standard ~ ~ ~
Cable,
in the
concrete
bonded
injection
encapsulated
electricallyisolated
×
×
×
¹
¹
~
~
with
unbonded
injection
standard +
encapsulated
electricallyisolated
×
×
×
×
×
restressable
and/or
replaceable
× ×
External
Cable,
out of
the
concrete
(or other
material)
with
bonded
injection
with
unbonded
injection
standard +
encapsulated
electricallyisolated
standard +
encapsulated
electricallyisolated
×
×
×
×
²
×
²
×
×
×
×
×
restressable
and/or
replaceable
× ²
×
For the other materials such as masonry, wood, etc., refer to conditions relative to concrete and take into account the
installation constraints, which may be of various types.
Notes ¹: This set-up features a fully-bonded cable. ²: Smooth ducts in polyethylene or polypropylene are the most common.
: Advised ~ : Possible × : Unadvised or forbidden

Annex 1 of the European Technical Approval No ETA-06/0006 10
The VSL Multistrand System's post-tensioning tendon ducts, for the most part with a circular cross-section, must
display an internal diameter large enough to provide for easy strands installation and adequate filling during
injection of the protective filling product.
With this objective, VSL recommends an internal duct diameter Øi ≥ 1.8 Αp , where Ap is the nominal crosssection
of the strands composing the unit. This relation is suitable for the case of threading the tendons by
means of pushing through strand by strand into the ducts installed prior to concreting. In the case of
prefabricated cables, it is authorized to adopt a duct with a smaller diameter. Moreover, during the calculations,
it is necessary to consider the distance (called eccentricity) existing between the center of the duct and the
center of gravity of the strand bundle cross-section.
The recommended duct dimensions, along with the corresponding eccentricity values, are given on Page 40 in
Chapter 6.
The ducts, depending on their type and capacities, may be provided on coil or in straight segments.
2.2.2 METAL DUCTS
The tendons are most often (as per the "STANDARD" solution) isolated from the concrete by means of
corrugated steel strip sheaths. According to Standard EN 523, they are either normal (Category 1), i.e. "normal
sheaths", or (Category 2), i.e. "rigid sheaths" but bendable by hand, with their characteristics being stipulated in
the standard.
Connections between coils or straight segments are performed by means of screwing a connector (coupler)
onto the two extremities to be connected. The sealing at the joints is done by either an adhesive ribbon or
thermo-retractable sleeves.
In certain applications (e.g. nuclear, offshore), the tendons are encased in smooth steel ducts. The most
frequently-employed tubes, whether welded or not, are thin (in compliance with the EN standards) and machinebendable.
The connections between segments are commonly performed by flaring one end and clamping the
other; the seal is generated by welding, thermo-retractable sleeves or adhesive ribbon.
2.2.3 PLASTIC DUCTS
In the case of stringent requirements as regards both corrosion protection and fatigue resistance of cables, it is
recommended to use the corrugated plastic duct VSL PT-PLUS ® . This duct may only be used inside the
concrete with a grouting and generates perfect bond between the tendons and the structure. It is recommended
for applications submitted to a particularly-aggressive environment or strong fatigue loads. The VSL PT-PLUS ®
duct complies with ETAG 013. The fitting between duct segments is introduced by means of mirror welding or
by connectors that provide for both the waterproofing seal and electrical isolation. This duct can be used with all
anchorage types E, CS, K, H. When used with CS-type anchorages, it allows to provide fully-encapsulated units
labeled CS "PLUS" as well as electrically isolated units labeled CS "SUPER". Such applications necessitate the
presence of rigid half-shells between the duct and its supports at all of the high points along cable path in order
to avoid any risk of perforation during stressing of the tendon.
More common ducts (sleeves or tubes) made of polyethylene or polypropylene can also be used. The
connections and seals between the coil or straight segments are introduced by either mirror welding or electroweldable
couplers, or other means. Plastic pipe in accordance with ETAG 013 / EN-compliant ducts are in fact
required. With an appropriate set of fittings, they may be used for applications involving encapsulated /
waterproof and electrically-isolated tendons.
2.2.4 ACCESSORIES FOR INLETS, BLEED VENTS AND OUTLETS
In internal (concrete) post-tensioning applications for structures composed of prefabricated elements, duct
continuity, regardless of duct type, is performed in alignment with the joints by means of a coupler fitting that
encompasses a set of rings inserted at the contact element duct end. These plastic accessories serve to
complete the seal.
Providing permanent protection by means of grout injection presupposes the possibility of intervening anywhere
along the cable path in order to adjust the filling and bleed any air, water, etc. that may be within the ducts. In
this aim, accessories for re-circulation, venting and bleeding are installed on the ducts. These basically
comprise shells or collars fastened onto holes in the ducts and connected to pipes with plugs opening onto an
accessible face of the structure. The following options are available:

Annex 1 of the European Technical Approval No ETA-06/0006 11
Duct Duct connection accessory
Inlet, venting, bleeding or outlet
accessory
Corrugated steel strip sheath Sealed plastic shell Plastic pipe
Smooth steel tube Welded pipes Steel tube or plastic pipe
VSL PT-PLUS ® duct Special "clipped" collar / coupler Plastic pipe
Plastic duct Electro-weldable collar or welded pipes Plastic pipe
Distributions of inlet, venting, bleeding and outlet points along the cable profile are selected based on a functionspecific
study of both the injection pattern and procedure.
2.2.5 CONNECTION WITH TRUMPETS
The strands, located within the ducts, must slightly dilate in the vicinity of the anchorages in order to pass
through the corresponding holes in the anchor head. This conical deviation is done in a transition zone called a
trumpet and is considered part of the anchorage element.
The trumpets of a specific anchor plate are of adequate diameters, with enough length and opening at the end
that allows for connection and alignment to the duct of the current zone.
The seal between the duct and trumpet is carried out using an adhesive strip, a thermo-retractable sleeve or a
connector designed as a duct accessory (e.g. a VSL PT-PLUS ® coupler).
2.3 CABLE LAYOUT
The cable layout patterns are not inherent to the VSL Multistrand System, but instead depend on the particular
project.
2.3.1 STRAIGHT LENGTHS BEHIND THE ANCHORAGES
In order for the strands not to display excessive deviation with respect to the anchor head support surface, it is
recommended to lay out a rectilinear segment in the back of the anchorage. This straight length in axial
alignment varies with the size of the prestressing units. The following has been specified as straight length Lmin
which includes both the anchor plate and the trumpet:
for Fpk < 2 MN Lmin = 0.8 m
for 2 MN ≤ Fpk ≤ 7 MN Lmin = 1.0 m
for Fpk > 7 MN Lmin = 1.5 m
2.3.2 RADIUS OF CURVATURE
In order for the ducts and tendons to be easily installed and handled, for the friction loss values to be respected
and for the actions upon deviations to be acceptable, it is recommended to limit the radius of cable curvature.
For internal (concrete) post-tensioning, in the cases of common deviations, VSL recommends verifying that:
R ≥ 100 Øi, where R is the radius of curvature and Øi = inside diameter of the duct.
This rule is appropriate for both corrugated steel strip sheaths of Category 2 (see Section 2.2.2) and the
VSL PT-PLUS duct (see Section 2.2.3).
When using corrugated steel strip sheaths of Category 1 (see Section 2.2.2) and smooth steel tube, R ≥ 3 m.
In more unique cases involving the use of smooth steel tubes, the radius of curvature may be significantly
reduced: R ≥ 20 Øi. Under such specific conditions, local concrete strength as well as stresses in strands
verifications must be performed.
Tendon sections curved in a U-shape at a tight radius to form an inaccessible end of the tendon named loop
anchorage (not considered to be an anchorage in the intent of ETAG 013) respect the following details :

Annex 1 of the European Technical Approval No ETA-06/0006 12
- duct in loop is either smooth or corrugated, diameter one size larger than in free length for ease
of connection (one fitting into other)
- radius of curvature in loop R ≥ max { 0.6 Fpk
; 0.6 m }, where R is expressed in meters and
Fpk expressed in MN.
For external (concrete) post-tensioning, in cases where a high-quality polyethylene tube and thickness adequate
for external cable use as defined in Appendix C.2 of the ETAG 013, the following values (based on ENV 1992-1-
5) should be respected.
Tendon Unit Minimum Radius (m)
6-7 2.0
6-12 2.5
6-19 3.0
6-27 3.5
6-37 4.0
6-43 4.5
6-55 5.0
While corrugated metal strip sheath can be bent by hand to almost any shape in space, machine-bent smooth
steel pipe can only be bent to a constant radius in one plane. The designer should take this into account when
specifying the tendon profile.
2.3.3 SPACING OF THE SUPPORTS AND TOLERANCES
The support heights underneath the duct are listed on the cable diagrams approximately every meter for a large
radius of curvature and every fifty centimeters for a small radius of curvature, in order to allow for duct
placement with the required level of precision.
Depending on the type of duct and its dimensions, the fastening fittings are sufficiently robust and close enough
such that the ducts and tendons will not exhibit displacements or deformations in excess of the allowed
tolerances.
The tolerances on cable positions in the concrete elements must respect the prescriptions stipulated in the draft
standard "pr ENV 13670-1".
Moreover, under all circumstances and in every direction, whenever a cable displays or potentially displays
deviation in the vicinity of an edge of concrete which could lead to spalling of concrete cover, an offset with
respect to the cable diagram in this direction is only tolerated provided that equilibrium reinforcing bars have
been provided over this zone.
2.3.4 STRAND CUT LENGTH
Since the anchorage has been fastened with respect to the structure undergoing post-tensioning, its space
consumption is limited to its specific volume. Strand length is strictly the length of the prestressed element
between the anchorages increased by the over length crossing the stressing jack(s).
These over length have been defined in the drawing on Page 39 in Chapter 6.
2.4 INSTALLATION OF DUCTS AND STRANDS
Depending on the size and layout of the worksite, the available space on site and the schedule of works, one of
the following solutions is to be adopted (for practical purposes and in order to list all installation possibilities,
only the case of an internal post-tensioning of a new concrete structure has been highlighted herein):
- Cables (both strands and ducts) fabricated in the plant and then delivered as needed at the worksite for
installation into the passive reinforcement;
- Strand bundles fabricated in a mobile workshop located adjacent to the worksite and then drawn either
before or after concreting into the ducts installed in the passive reinforcement;
- Tendons composed by pushing through strand by strand before or after concreting into the ducts installed
in the passive reinforcement.

Annex 1 of the European Technical Approval No ETA-06/0006 13
2.5 PROVISIONAL PROTECTION AND LUBRICATION
The oiling or greasing of strands, exclusively by means of non-dangerous substances, is performed:
- in the aim of providing provisional protection against corrosion from the time of leaving the plant until
permanent protection has been achieved (grouting of the cable);
- in the aim of lubrication since the friction loss of oiled strands in the ducts during stressing is lower.
With this same objective, other products serving to reduce friction loss may be used, as long as they are
recognized as non-dangerous, can be easily applied and remain inert in the presence of permanent protection
(and the eventual bond to the structure),.
It is necessary to point out that:
"In addition to the specific clauses relating to dangerous substances contained in this European Technical
Approval, there may be other requirements applicable to the products falling within its scope (e.g. transposed
European legislation and national laws, regulations and administrative provisions). In order to meet the
provisions of the EU Construction Products Directive, these requirements need also to be complied with, when
and where they apply."
2.6.1 FRICTION LOSSES
2.6 CACULATION ELEMENTS
where μ is the friction coefficient (over the curve) between the strands and the duct, θ the sum of the
angular deviations of the cable over the distance x, and k the unintentional deviation (per unit length) affecting
the cable path,
it is recommended to adopt the numerical values of μ and k according to Eurocode 2 (EN 1992-1-1). They can
be summarized as follows:
Application μ (rad -1 ) k (rad/m)
Internal (concrete) cable with corrugated steel strip sheath 0.17 - 0.19 0.005 - 0.010
Internal (concrete) cable with smooth steel tube 0.16 - 0.24 0.005 - 0.010
Internal (concrete) cable with VSL PT-PLUS duct 0.12 - 0.14 0.005 - 0.010
External (concrete) cable with smooth steel tube 0.16 - 0.24 0
External (concrete) cable with plastic duct 0.12 - 0.14 0
Internal (concrete) cable with individually greased and sheathed strands 0.05 0.020 – 0.060
External (concrete) cable with individually greased and sheathed strands 0.05 0.020 – 0.060
The interval limit values encompass both lubricated and non-lubricated strands.
The values of k are zero for cables outside the concrete.
2.6.2 BASIS FOR EVALUATING ELONGATIONS
The calculation of elongations for stressing purposes presumes that the tension curve within the strands along
the cable just before locking of the anchorage is known, i.e. fpo (x).
The measurable elongation upon stressing at the back of the jack for the live end anchorage under
consideration, where x = 0, may be written as follows:

Annex 1 of the European Technical Approval No ETA-06/0006 14
where, in the second member,
- for the 1 st term:
L j : length of the strands in the stressing jack.
fpo (x) ~ (1 + ka). fpo,o = constant
where fpo,o: stress in the strands upon stressing at x = 0,
ka: friction loss in the anchorage, which may be neglected for this purpose;
- for the 2 nd term:
La: length of the concerned tendon = length from the live end anchorage to the MIN (fpo(x)), i.e. the abscissa of
the strands cross-section not moving;
- for the 3 rd term:
negligible in the majority of cases (except if stresses in the concrete resulting from prestressing are high);
- for the 4 th term:
in the case where the cable is terminated by a fixed external anchorage whose wedges were manually pre-set
(common case), a draw-in g’ of these so-called wedges on the order of 3 mm must be incorporated.
In simplifying and defining: fpo,m, the average stress over the concerned strands length, the following is
obtained:
On the worksite during stressing, elongation due to tendon slack should be eliminated from the reported value
with appropriate procedures (e.g. taking into account elongations only once the tendon has been stiffened inside
its duct).
Note : ka : friction losses in the anchorages are expressed in Section 4.2.1
2.6.3 SETTING OF ANCHORAGE WEDGES
A 6-mm draw-in of the wedges is considered; this value remains constant for all units and is applicable to all
anchorages and all types of wedges.
When an adjustment must be conducted, the insertion of a suitable split shim between the anchor head and its
anchor plate, makes it possible to compensate for the wedge draw-in up to the shim thickness.
In this case, the re-tensioning force must not exceed Pmax, which is the maximum force authorized during unit
stressing. If upon initial tensioning Po,o < Pmax, compensation for the wedge draw-in may thus be complete. If
however upon initial tensioning Po,o = Pmax, an uncompensated wedge draw-in of 1 to 2 mm must be
incorporated.
The split shim is made of same material as anchor plate E and that diameter of hole is the same as specified in
E or CS plate (depending of which anchor is used).
Note : compression fittings are without significant setting.

Annex 1 of the European Technical Approval No ETA-06/0006 15
CHAPTER 3
3. ANCHORAGES
ANCHORAGES
3.1 DESCRIPTION OF ANCHORAGE COMPONENTS
VSL Multistrand System anchorages make use of a set of standard elements, to be categorized as follows:
3.1.1 LIVE END / DEAD END ANCHORAGES
Live end (active) and dead end (passive) anchorages comprise:
- Anchor plates and trumpets:
Common anchorage plates and duct-transition trumpets exist in accordance with two models:
- the "E" model composed of a simple plate made of steel according to Standard EN 10025. The most
frequently-used steel is S235JRG2 and the E trumpet is made of steel sheet;
- the "CS" model composed of a cast iron matrix with spheroidal graphite in accordance with Standard
EN 1563, made composite with a very high-strength mortar. The cast iron used is EN-GJS-500-7U. The
CS trumpet is made of plastic and can be ended by an appropriate ancillary attachment for connection
to the VSL PT-PLUS ® duct. The CS trumpet can also be associated with E anchor plate model.
- Anchor heads:
The basic anchor heads may be found in two models:
- the "E" model, associated with plate E, formed from a steel rod, with quenching and tempering
according to Standard EN 10083-2. The most frequently-used steel is C45;
- the "CS" model, associated with plate CS, formed from a steel rod, with quenching and tempering
according to Standard EN 10083-1 and then machined or forged to achieve variable thickness. The
most frequently-used steel is 42CrMoS4.
The conical holes are machined on transfer equipment and exhaustively controlled.
- Wedges:
The wedges are trimmed in alloyed steel for cementation according to Standard EN 10084, then cleaved into
parts and then treated. The most frequently-used steel is 20NiCrMo2-2. These elements are available in two
models:
- the "W6N" (or "S") model, with two independent parts;
- the "W6N" (or "S") 3C model, with three parts attached by means of a retaining ring.
For each of the models, the wedges are specified according to two types, adapted to strand diameters, along
with the 6N wedges for the 0.6" or T15.2 strands and the 6S wedges for the 0.6"S or T15.7 strands. The S (or
super) wedges are differentiated from the N (normal) wedges by the presence on the plane face, which remains
apparent, of a grooved trim. These wedges are all submitted to rigorous controls.
Both the VSL Multistrand System and VSL Slab System (see Annex 2) wedges are identical.
- Protective caps:
In order to enable injecting permanent protection and ultimately contributing to protecting the anchorage, three
cap models to be used with the plate are available:
- the provisional cap designed to contain the injection product for the permanent protection of the zone.
Following the curing period, this cap is recycled for reuse; the injection product must be a rigid grout and
then the anchorage block-out must be filled with concrete;
- the permanent metallic cap, containing the anchor head and the protection product, which is left in place
after injection;
- the permanent plastic cap, containing the anchor head and protection product, which is also to be left in
place after injection. This cap has been designed in particular for sealed and electrically isolated cables.
Permanent caps are obviously required in all cases calling for the injection of a flexible protection product.
Provided a few precautions have been taken against corrosion of the metallic parts, the permanent caps may be
left apparent; moreover, permanent caps can also be used as temporary caps.

Annex 1 of the European Technical Approval No ETA-06/0006 16
3.1.2 COUPLERS
The couplers rely, for the second-phase cable, upon reliable anchorage components that are supported on the
installed anchor head including connection grooves.
This setup consists of compression fittings, composed of a hard steel wire hoop wound in a spiral and a bushing
sleeve cut into the steel to allow for quenching and tempering, as stipulated in Standard EN 10083-2. The type
of steel used is C45. The hoop is assembled on the strand, and then the fitting is seamed by means of coldthreading
on the assembled unit.
3.1.3 PRESENTATION AND PACKING OF ANCHORAGES
Given that strand placement only takes place in a rather generalized manner following concreting, the delivery
of anchorages on the worksite entails:
(only the most common case of internal (concrete) post-tensioning of a new structure will be highlighted herein)
1. Delivery of the anchor plates along with the ducts for placement within the passive reinforcement, and
fastening of the plates to the formwork. These anchorage parts are delivered tagged for identification
either on pallets or in bulk.
Following concreting and curing:
2. Delivery of the anchor heads and wedges along with the strands to be threaded, installation of the
anchor heads, stressing and grouting of the permanent cable protection. These anchorage components
are delivered tagged for identification, packaged and protected (the same applies for the strands).
3.2 ORGANIZATION OF SUPPLY QUALITY
The fabrication of anchorage components of post-tensioning system and especially those designed for the VSL
Multistrand System is conducted in compliance with the specifications, production and control procedures laid
out in the present ETA and associated documents.
The control procedures in effect for anchorage Component Manufacturers, to the same extent as those adopted
by the PT Specialist Company, serve to ensure the traceability of the components all the way through to their
delivery on site. It is to be recalled that the basis for evaluating these procedures and the supervision of their
application have been defined in Chapter 8 and its Annex E of the ETAG 013.
It should also be recalled that prior to installation, the compliance of all delivered components, by means of both
identification and visual inspection of their state, must be performed by the PT Supervisor.
3.3 IMPLEMENTATION OF VARIOUS ANCHORAGES
The implementation of VSL units must be assigned to a competent staff member and involve technical
management personnel within the PT Specialist Company or a PT Supervisor certified by this company.
Anchorage placement in accordance with model prescriptions is handled as follows (for practical purposes, only
the most common case of internal (concrete) post-tensioning of a new structure has been highlighted herein):
3.3.1 TYPE "E" AND "CS" LIVE END ANCHORAGES
The anchor plates and trumpets are fixed to the formwork and connected to the ducts which have been placed
at the time of installation of the passive reinforcement; they are thus incorporated into the structure or structural
element upon concreting.
It should be noted that for the "E" plates, the possibility exists to install them on a previously-completed concrete
facing by means of inserting a flexible and durable joint between the plate and concrete or installing them on a
metallic surface.
On the other hand, the "CS" plates may only be installed into a concrete block cast around the plates.

Annex 1 of the European Technical Approval No ETA-06/0006 17
The arrangement of injection holes vary according to the anchorage models and structures and can either open
onto the front face or may use pipes in order to open onto other faces of the structure.
The anchor heads and wedges are positioned immediately before stressing, a step which serves to avoid
polluting the parts.
Anchorages used with monostrands (individually greased and sheathed) include sealing between anchor head
and monosheaths to close the current grouted zone and to confine greased protection in the anchorage zone
(e.g. with neoprene disk or plastic sleeve).
Anchorages used with both isolating rings (to be inserted between the head and plate) and isolating plastic
caps, enable constituting electrically isolated tendons, such as the CS "SUPER" type units. The "E" anchorages
can also be used for electrically isolated tendons when using the CS plastic trumpet.
As for force losses in the anchorages during stressing, see Section 4.2.1: "Force Measurements".
3.3.2 TYPE "E" AND "CS" DEAD END ANCHORAGES
The placement of these anchorages is performed as indicated in Section 3.3.1. Once the anchor head has been
installed, before stressing at the other end, the wedges are pre-locked using a wedge tool. The anchorage then
remains accessible throughout the stressing phase for observation. These anchorages also enable generating
electrically isolated tendons.
3.3.3 TYPE "H" BOND ANCHORAGE
The load transfer to the structure is based primarily on the bond of dilated strands within the concrete over a
straight segment length and the anchorage by an onion (curvature of wires) at the strand end.
Upon exiting the duct, the strands are gradually deviated towards two positioning and maintenance grids. The
duct end is reinforced with a ring.
The entire anchorage assembly is solidly fastened to the passive reinforcement.
Following assembly of the injection tube, the sealing between duct end and strands is ensured by means of
resin packing at the level of the ring.
The proper working of the anchorage necessitates degreasing the strands on the bond length, along with careful
concreting over this length using a concrete whose aggregate diameter does not exceed 30 mm.
3.3.4 TYPE "K" COUPLER
When a structure must be built in several phases, especially when setting up the scaffolding and formwork over
the entire length of the structure proves impossible, it may be wise to stress and anchor certain cables over a
fraction of their length and then extend them through the use of a coupler.
Once the structure has been completed, the coupler may or may not be inside the concrete.
Installation of the coupler proceeds for the active part as defined in Section 3.3.1 for the "E" or "CS" type of live
end anchorage, with the installed anchor head being the "K" head fitted with grooves for peripheral coupling.
For the passive part of the coupling, the installation takes place prior to concreting of the zone; the strands
exiting the duct are deviated through a ring towards the "K" head; they are fitted with compression fittings and
placed into the designated grooves. A strapping serves to maintain them in position and a trumpet/sleeve (made
of either sheet metal or plastic) isolates the coupler from the concrete, thereby making it possible to transmit the
prestressing force through the joint.
A vent at the apex of the trumpet/sleeve allows for accurate filling during grouting.

Annex 1 of the European Technical Approval No ETA-06/0006 18
3.4 ANCHORAGE ARRANGEMENTS
According to categories of use, referring to Section 1.4.1, arrangements of anchorage components are descri-
bed in the following table :
Uses Components
Anchorages E CS H K
Head
Plate
Trumpet Cap
Head
Plate
Trumpet Cap Coupler
Plate
Trumpet
internal bonded cable with metal duct E E T(2) CS CS T(2) H K (5) M(6)
internal bonded cable with plastic duct E CS T(2) CS CS T(2) H K (5) M(6)
internal unbonded E E PM(3) CS CS PP(3) K (5) M(6)
external bonded cable E E PM(3) CS CS PP(3) H K (5) M(6)
external unbonded cable E E PM(3) CS CS PP(3) K (5) M(6)
tendon for various material (ext. cable) E E PM(3) K (5) M(6)
restressable tendon E E PM(4) CS CS PP(4)
exchangeable tendon E E PM(4) CS CS PP(4)
encapsulated tendon (leak tight) E CS PM(3) CS CS PP K (5) M(6)
electrically isolated tendon E(1) CS PP CS(1) CS PP K(1) (5) P(7)
Notes : 1 : plus isolating shim in between head or coupler and plate,
2 : T (as temporary) Provisional cap, Permanent (P) cap can be used,
3 : Permanent Metallic (PM) or Permanent Plastic (PP) cap,
4 : Permanent Metallic (PM) or Permanent Plastic (PP) cap, special cap housing to preserve strand over-lengths
should be used,
5 : See E or CS anchor plate and trumpet of first-phase cable,
6 : Metallic (M) sleeve (cap), Plastic (P) sleeve can be used,
7 : Plastic (P) sleeve (cap)
3.5 GEOMETRICAL AND MECHANICAL USE CONDITIONS
For the seating and installation of anchorages, certain construction-related conditions must be verified.
3.5.1 CLEARANCE BEHIND ANCHORAGES
In order to facilitate jack placement and simplify the stressing procedure, a free space must be allocated behind
the anchorage.
These dimensions are given in the drawing Page 39 "Block out dimensions for anchorages type E and type CS,
Clearance requirements" in Chapter 6.
3.5.2 CONCRETE COVER AND ANCHORAGE SPACING
Introducing post-tensioning forces into the structures takes the form, within the anchorage zones, of
concentrated forces applied onto the plates. The high stress values encountered underneath the anchor plates
necessitate certain construction-related measures. For the concrete structures:
- The anchorages must be laid out at a sufficient distance from the nearest edge of the concrete (cover) and
respect a spacing between anchorages (centre to centre) that will be specified below.
- A bursting reinforcement must be set up in front of the plates; this local (surrounding anchorage body) zone
will be defined in Section 3.6.
- The concrete in the vicinity of the plates must be especially homogeneous and display, at the time of
stressing, an adequate level of strength.
- A general (surrounding local zone) zone must be defined by the project designer and laid out in front of the
anchorage plates within the structure, thereby reducing the concentrated forces and distributing them over
the concrete cross-section, in compliance with the design rules.
As stated above and in considering a maximum prestressing force P(t,x) at the time of stressing (t = 0) at the
anchorage (x = 0), thus called P(0,0) ≤ Pmax, for the normal anchor plates and P(0,0) max = Pmax, the following are
defined:
Force in the cable, at the anchorage on the concrete side, before load transfer to anchorage.
Sleeve
(cap)

Annex 1 of the European Technical Approval No ETA-06/0006 19
b0 and b’0 are the distances between the anchorage axis and the edge of the block tested. These values are
given in the tables here after.
The reinforcement required to prevent bursting and spalling in anchorage zones is determined in relation to a
rectangular prism of concrete, known as the primary regularisation prism, located behind each anchorage. The
cross section of the prism associated with each anchorage is known as the impact rectangle.
The impact rectangle has the same centre and the same axes of symmetry as the anchor plate (which should
have two axes of symmetry).
The impact rectangle with dimensions c x c’ has the same area as the block tested A = 4 x b0 b’0 and the same
aspect ratio (variation of -15% is allowed in one direction).
b 0
b’0
cmin,rect = 0.85 x 2 b0 ; c’ min,rect = 0.85 x 2 b’0
cmin and c’min taking into account dimensions of bursting reinforcement are given in the tables here after, then
c ≥ cmin or c’ ≥ c’min (1)
and c x c’ = A = 4 x b0 b’0 (2)
It should be noted that application of cmin may require adaptation of the local anchorage zone reinforcement in
accordance with the applicable Eurocodes and national regulations, see Chapter 3.6.
Rules for centre distance and edge distances of anchorages:
Impact rectangles associated with anchorages located in the same cross section should not overlap.
In addition, they should remain inside the concrete. Taking into account the concrete cover, we obtain the
distance to edge in the two directions :
c
c '
+ cov er − 10mm
and + cov er − 10mm
2
2
Note: 10 mm is the concrete cover in the tested block (except for H anchorage block using 25 mm).
For anchorage spacing, refer to equations (1) and (2)
Type "E" anchor plates,
for f cm(t) ≥ 23/28 N/mm 2
Units 6-1 6-2 6-3 6-4 6-7 6-12 6-15 6-19 6-22 6-27 6-31 6-37 6-43 6-55
u = u’ mm (1) 75 110 135 160 205 270 300 340 370 410 435 480 520 580
2b0 = 2b’0 mm (2) 115 165 205 235 310 410 455 515 550 610 655 715 775 875
cmin = c’min mm
100 140 175 200 265 350 385 440 470 520 555 610 665 745
(1) Sizes of anchor plate
(2) Sizes of test block
Type "CS" anchor plates,
for f cm(t) ≥ 28/35 N/mm 2
Units 6-7 6-12 6-19 6-27 6-31 6-37
∅ u mm (1) 222 258 300 360 390 420
2b0 = 2b’0 mm(2)
( ) ( ) cmin = c’min mm
310 410 515 610 655 715
(1) Sizes of anchor plate
(2) Sizes of test block
265 350 440 520 555 610
Dimensions A and B (u and u’) for type “H” anchorages and minimum spacing either A + 25mm or B + 25mm,
are specified on the drawing Page 36. Dimensions of concrete sections are given on Page 37 in Chapter 6.

Annex 1 of the European Technical Approval No ETA-06/0006 20
During cable stressing, the concrete in front of the anchor plates must have reached an adequate strength level,
as previously indicated and as a complement, it would be necessary to specify:
for the case of specified anchor plates on concrete,
stressing to 100% of P(o,o) max = Pmax is not permitted if fcm(t) < 23/28 N/mm 2 for the "E" anchorages and
28/35 N/mm 2 for "CS" anchorages, regardless of the anchorage configuration within the structure.
It remains possible however to partially stress the tendon. In the case of tensioning to 50% of the maximum
value at the anchorage for example, the strength of concrete f cm(t) may be reduced to approximately 2/3 of the
values indicated above for total stressing.
As noted above for those anchorages that rely upon bond alone, i.e. type "H" anchorages, strength of concrete
within the zone during stressing must be: fcm(t) ≥ 28/35 N/mm 2 .
From a general standpoint for unique cases (e.g. when using materials other than concrete), the project
designer will apply the pertinent Eurocodes with Pdesign ≥ 1.1 Fpk to design anchorage and deviation zones
(contact may be made with the VSL organization, which will provide the proper advice as regards experimental
work and developments).
3.6 BURSTING REINFORCEMENT
As mentioned previously, a bursting reinforcement must be laid out in the local anchorage zone.
For both the "E" and "CS" type anchorages, this reinforcement is split between a spiral and orthogonal
reinforcement (stirrups). The spiral reinforcement defined on the drawings in Chapter 6 displays a large enough
pitch of the thread to allow for adequate concreting of the zone.
It is recommended to proceed with this layout as stipulated in the approval whenever both the cover and
strength conditions have been minimized.
As foreseen by this ETA, the local anchorage zone reinforcement specified in this ETA and confirmed in the
load transfer tests, may be modified for a specific project design if required in accordance with national
regulations and relevant approval of the local authority and of the ETA holder to provide equivalent
performance.
In the case of grouped anchorages, it is permitted to combine the reinforcement of the individual anchorages.
The chosen combination must conserve the dedicated steel cross-sections in all directions. In the case of a
unique arrangement in the vicinity of the plates, it is also possible to replace the spiral with a combination of
bars that contain equivalent cross-sections in all directions and that are configured at the same depth with
respect to the plate.
In all cases, the bursting reinforcement must be complemented by a reinforcement in the general anchorage
zone for equilibrium designed by the project designer in accordance with typical design rules.
Similarly, in all cases, the contractor responsible for concreting must ensure that the density and layout of
reinforcement within the anchorage zone allow for adequate and homogeneous concreting of the entire zone.
Similar to every other type of anchorage, VSL type H-anchorage requires a local anchorage zone reinforcement
split between a spiral and orthogonal reinforcement (stirrups). This reinforcement is defined on the drawing in
Chapter 6.

Annex 1 of the European Technical Approval No ETA-06/0006 21
CHAPTER 4
4. TRESSING
STRESSING
4.1 STRESSING EQUIPMENT
The VSL equipment used for cable stressing is composed primarily of stressing jacks, hydraulic power packs
(commonly called pumps) and the associated set of measurement instruments or acquisition system.
4.1.1 STRESSING JACKS
Tendons are stressed by means of VSL stressing jacks.
This equipment consists of double acting jacks with a central hole that enables stressing the cable in one or
several stages and then, if need be, to de-stress the cable. Their primary characteristics will be defined below.
In sequence starting from the anchorage, these jacks are composed of:
- 1 nose (chair ring) at the front resting upon the anchor head,
- 1 body or cylinder, including a piston with a central hole, resting upon the chair ring,
- 1 battery composed of metallic tubes fastened to the inside of the hole that guide strands behind the jack,
and
- 1 pulling anchor head behind the piston, with a gripper plate for facilitating the procedure of stressing by
stages. The ungripping of the jack anchorage is performed automatically.
List of VSL jacks:
Designation ZPE 30 60 7A 12/St2 200 19 460/31 500 500K 750 1 000 1250
Length mm 720 615 690 550 960 750 580 1 000 610 1 185 1 200 1 290
Diameter mm 140 180 280 31 315 390 485 550 508 520 790 620
Weight kg 28 74 115 151 305 294 435 1 064 450 1 100 2 290 1 745
Maxi force kN 320 632 1 064 1 850 2 000 2 900 4 660 5 000 5 000 7 500 10 000 12 500
Pressure bar 550 500 523 598 614 580 580 560 580 600 553 577
Ram area mm² 5,832 12,640 20,360 30,940 32,570 50,030 80,400 89,460 86,200 124,700 180,950 216,800
Stroke mm 250 250 160 100 300 100 100 200 100 150 200 150
The drawing in Chapter 6 indicates the clearances to be introduced around the anchorages and at the ends of
the post-tensioned structures in order to facilitate installation.
For the purpose of implementing all the particularities and options, the VSL stressing equipment comprises a
series of modular and compatible accessories; as such, a broad range of tools for these jacks is available by
VSL.
Included herein would be the jack chair ring, the over-stress chair ring, the de-stress chair ring, etc.
4.1.2 HYDRAULIC PUMPS
The VSL pumps comprise the assembly of hydraulic components including: pumps, distributors, nozzles and
safety valves. The pumps are typically driven by electric motors.
The pumps themselves have been dimensioned for normal stressing speeds and contain safety measurement
devices that depend on the specific application.
4.1.3 MEASUREMENT INSTRUMENTS AND SYSTEMS
The VSL force and elongation measurement instruments or systems serve to control with precision the stressing
operation and display the set of results obtained.

Annex 1 of the European Technical Approval No ETA-06/0006 22
4.2 PROCESSES OF STRESSING AND CONTROL PROCEDURE
Before proceeding with cable stressing, a certain number of preconditions must be met, in particular:
- all pertinent safety rules and recommendations must be fully known;
- the force targets along with the corresponding values of elongation; moreover, tolerances must be known
by the PT Supervisor, who will have applied any eventual necessary adjustments to these values in order to
account for parameters specific to the equipment and anchorages;
- the procedure to be adopted in the event of a value beyond the tolerance threshold or any other
unanticipated incident must be known;
- the order in which the post-tensioning cables are to be stressed must be specified;
- the stressing equipment (including measurement instruments) must comply with guidelines furnished in the
present ETA;
- the required strength of concrete (or other component material) of both the structure and anchorage zone
undergoing stressing must be verified;
- the loading and support states of the structure associated with the stressing phase must also be verified;
- the over lengths of the strands for stressing must remain perfectly clean.
The point should be recalled that during the stressing process, it is strictly forbidden to be positioned behind the
jack or within its immediate vicinity. The same precautions must be taken for the area in the back of the deadend
external anchorages.
One of the VSL system's key characteristics lies in its wedge-locking process. Given that the wedges remain in
constant contact with the strands during stressing, the locking operation does not require any accessory device.
4.2.1 FORCE MEASUREMENTS
The measurement of force in the cable, as transformed into pressure measurement in the jack, is generally the
assigned objective herein.
The pressure existing in the jack chamber is indicated by the manometer installed on the pump, with the
eventual possibility of exercising controls on the jack. The manometers used (Accuracy 1%), regularly
recalibrated using a scale, feature a guaranteed precision of 1% of their maximum pressure, which tends to lie
at 600 bars; these instruments thereby provide a precision of 6 bars over the entire manometer scale.
In order to obtain the effective force onto the structure, the force resulting from the manometer reading is
corrected for losses inside the jack as well as for losses due to friction of the strands in the anchorage.
Losses inside the jacks are identified from intrinsic hardware data. Although they contain an independent
pressure term and another closely-proportional term, submitted to the maximum pressure reached upon
completion of the stressing operation, the losses inside jacks are solely expressed in proportional terms and
vary from 1% to 3%.
The losses in active anchorages E and CS (or K), named ka, are due to friction of the strands deviated on the
components and, depending on the specific anchorage, vary between 1% and 2%.
4.2.2 ELONGATION MEASUREMENTS
The measurement of cable elongation is generally a control measurement that provides information on cable
behavior during stressing.
As for elongation measurements, an index is installed on the tendons. During stressing, elongations are then
deduced from measurements of the displacement of this index. Since the onset of displacements combines the
seating of tendons in their ducts with their actual elongation, the elongation during initial displacements is
obtained by means of extrapolating the pure elongations occurring subsequently.
The various pressure-elongation relations noted during the cable stressing phases are recorded on the
stressing data sheets, which are to remain available.
Section 2.6.2 provides a recap of the elongation evaluation basis used during the stressing operation.

Annex 1 of the European Technical Approval No ETA-06/0006 23
5. INJECTION CHAPTER AND 5 5 SEALING
INJECTION AND SEALING
5.1 GENERAL INFORMATION
The nature and composition of injection products for the permanent protection of tendons and anchorages and
for their eventual bonding to the structure are not inherent to the prestressing process; instead, they depend on
the project and the structure's assigned purpose.
The products involved must not be a threat to the hygiene, health and the environment.
In addition to the specific clauses relating to dangerous substances contained in this European Technical
Approval, there may be other requirements applicable to the products falling within its scope (e.g. transposed
European legislation and national laws, regulations and administrative provisions). In order to meet the
provisions of the EU Construction Products Directive, these requirements need also to be complied with, when
and where they apply.
5.2 INJECTION PRODUCTS
The products used for the permanent protection of post-tensioning tendons and anchorages implemented by
means of injection may be categorized as follows:
5.2.1 PRODUCTS FOR BONDED CABLES
When it is sought to bond the tendon to the structure, the products or grouts for bonded injection are with a
hydraulic cement base:
These products may pertain to common grouts defined in the standard EN 447 or special grouts that make use
of performance-enhancing admixtures. In some regions of the EU, unfavorable climatic conditions or other
conditions impose the application of special grouts according to ETAG 013.
Completion of the tendon envelope at the end of the anchorages may be provided by means of either temporary
or permanent grouting caps.
The concreting of block out is only strictly necessary when using temporary grouting cap (whether recycled or
not). Should the permanent grouting cap be left apparent, the metallic parts must be protected against
corrosion, see Section 3.1.1.
5.2.2 PRODUCTS FOR UNBONDED CABLES
When it is not sought to bond the tendon to the structure in order, for example, to be able to maintain the tendon
accessible, the unbonded injection products are as follows:
- with a grease base, as defined in Annex C.4.1 of the ETAG 013,
- with a wax base, as defined in Annex C.4.2 of the ETAG 013.
In this case, plugging the tendon envelope at the anchorages is still provided by permanent waterproof injection
cap. The concreting of the block-out is not strictly necessary here, see above and Section 3.1.1.
Those products for bonded or unbonded injection covered by a European Technical Approval may also be
employed in accordance with the prescribed set of uses.

Annex 1 of the European Technical Approval No ETA-06/0006 24
5.3 INJECTION EQUIPMENT
The injection equipment has been adapted to the specific products to be injected.
For the cement-based grouting, the VSL injection equipment is composed for the most part of mixers and
pumps integrated into a single device that enables preparing the grout and performing the injection. This
equipment makes it possible to allocate with precision the grout components and to obtain a perfectlyhomogeneous
mix. The pump installed in the injection equipment has been designed for continuous injection at
a grout progression speed of the same order of magnitude regardless of the units used.
For some applications, vacuum pumps that allow for depressurization inside the ducts have been included,
thereby facilitating progression of the grouting.
For the unbonded products such as grease or petroleum wax, the VSL injection equipment is composed of
melting devices or heaters, stirrers and pumps. Depending on the application, these components are either
integrated or separated on the worksite in accordance with implementation specifications.
5.4 INJECTION AND CONTROL PROCEDURE
Before proceeding with the injection of permanent cable protection, a certain number of conditions must be
fulfilled and in particular:
- The injection product must comply with the terms of the present ETA and the ETAG 013;
- The injection equipment must comply with indications laid out in the present ETA,
- The waterproof sealing of the tendon and anchorage envelopes (ducts, fittings, rods and caps) must be
verified,
- The climatic conditions and temperature of the structure must satisfy use conditions of the injection product.
The primary controls conducted during injection consist of verifying the adequate filling of the duct by means of
rods, bleed vents and outlets laid out all along the cable path and verifying that the product discharged by the
vents or outlets displays the required properties.
Grouting procedures and grouting surveillance shall be carried out according to EN 446.
As an initial approach, the injection product quantities per unit cable length will be derived from:
[(internal duct section area - tendon section area) × (unit length)] × (1 + ξ), where ξ is such that: 0.10 ≤ ξ ≤ 0.20
in order to consider worksite losses, the shape of the duct and eventual corrugations.
The various phases and parameters associated with cable injection are to be recorded on the injection data
sheets, which are to remain available.
5.5 SEALING
The continuity of protection against all types of aggressions must be ensured all along the cable up to and
including the anchorages.
The protection measures introduced for this unique zone, which is often located at the extremity of the structure
and submitted to external aggressions determined during the design phase, must be effective.
Refer to the section entitled "Protective Caps" in Section 3.1.1 "Live end / Dead end anchorages" and to the
corresponding drawings on Page 29 in Chapter 6.
The concreting of block-out in the anchorage zone with surface treatment and eventual reinforcing bars
represents the most widespread solution. Moreover, it may be advantageously complemented by a waterproof
lining that prevents against all risks of infiltration of fluids that may runoff on the face of the block-out.
The permanent metallic caps (if protected by means of galvanization, paint, etc.) or plastic caps may be left
apparent.

Annex 1 of the European Technical Approval No ETA-06/0006 25
CHAPTER 6
SCHEMATIC DRAWINGS
(dimensions expressed in mm)
Title Page
STANDARD ANCHORAGE PARTS :
Wedges, Compression fitting 26
Anchor heads Type "E" 27
Anchor heads Type "CS" 28
Protective caps for anchorages Type "E" and Type "CS" 29
ANCHORAGE TYPE "E"
Categories of use arrangements 30
Sizes 31
Bursting reinforcement 32
ANCHORAGE TYPE "CS"
Categories of use arrangements 33
Sizes 34
Bursting reinforcement 35
ANCHORAGE TYPE "H"
Sizes and bursting reinforcement 36
Arrangement and minimum dimensions of concrete sections 37
COUPLER TYPE "K"
Sizes 38
BLOCK OUT DIMENSIONS FOR ANCHORAGES TYPE "E" AND TYPE "CS"
CLEARANCE REQUIREMENTS
DUCTING 40
39

Annex 1 of the European Technical Approval No ETA-06/0006 26
STANDARD ANCHORAGE PARTS
WEDGES
COMPRESSION FITTING

Annex 1 of the European Technical Approval No ETA-06/0006 27
STANDARD ANCHORAGE PARTS
ANCHOR HEADS TYPE E

Annex 1 of the European Technical Approval No ETA-06/0006 28
STANDARD ANCHORAGE PARTS
ANCHOR HEADS TYPE CS

Annex 1 of the European Technical Approval No ETA-06/0006 29
STANDARD ANCHORAGE PARTS
PROTECTIVE CAPS FOR ANCHORAGES TYPE E AND TYPE CS
6-7
6-12
6-19
6-27
6-31
6-37
Unit ØA B C D
6-3 78 165 30 63
6-4 89 190 40 62
6-7 116 230 40 63
6-12 155 290 50 63
6-15 185 310 40 63
6-19 190 340 40 63
6-27 230 370 40 63
6-31 235 450 40 65
6-37 260 480 40 65
6-43 290 540 40 65
6-55 320 600 40 65
Unit ØA B C D
6-3 103 160 50 110
6-4 119 195 50 115
6-7 153 255 60 120
6-12 190 310 70 135
6-15 207 320 70 145
6-19 223 325 70 155
6-22 244 345 70 160
6-27 258 375 70 170
6-31 287 405 70 180
6-37 309 480 90 195
6-43 346 535 90 205
6-55 389 585 90 220
Unit ØA ØB C(CS)
209
243
283
341 279 140
370 300
396
170
201
234
325
112
113
114
150
160
C(E)
112
130
150
180
210
210

Annex 1 of the European Technical Approval No ETA-06/0006 30
ANCHORAGE TYPE E
CATEGORIES OF USE ARRANGEMENTS
PRINCIPLES:

Annex 1 of the European Technical Approval No ETA-06/0006 31
ANCHORAGE TYPE E
SIZES
Units
A ØB C ØD E F G ØH ØI
6-1 75 18 10 53 50 80 150 25 21/25
6-2 110 50 10 90 50 80 200 50 21/25
6-3 135 56 15 95 50 80 205 55 21/25
6-4 160 65 20 110 55 85 210 60 21/25
6-7 205 84 30 135 60 90 320 72 28/32
6-12 270 118 40 170 75 105 500 92 28/32
6-15
6-19 340 150 50 200 95 125 640 107 28/32
6-22 370 172 55 220 100 130 745 122 28/32
6-31 435 192 65 260 120 150 755 142 28/32
6-37 480 215 75 280 135 165 905 155 28/32
6-43
6-55
520
580
248
255
80
95
300
340
145
160
175
190
1030
1045
165
185
28/32
28/32
J K
86
136
125 M10
150
210
265
280
300
360
435
Ø5
Ø5
M16
M16
M16
305 143 45 190 85 115 585 97 28/32 275 M16
6-27 410 185
J : Fixation holes (to shuttering) spacing.
M16
M16
60 240 110 140 690 132 28/32 330 M16
M16
M16
490 M16
540 M16

Annex 1 of the European Technical Approval No ETA-06/0006 32
ANCHORAGE TYPE E
BURSTING REINFORCEMENT
Units
6-1
6-2
6-3
6-4
6-7
6-12
6-15
6-19
6-22
6-31
6-37
6-43
6-55
Reinforcement for concrete with f cm(t) 23/28 N/mm² when stressing
ØN
8
10
10
10
12
16
16
16
16
20
20
20
SPIRAL REINFORCEMENT ORTHOGONAL REINF.
n P
1
2
2
3 65
4
5
7
8
10
9
11
12
70
60
75
60
70
60
60
6-27 16 9 55 545 68
16
55
65
60
60
Reinforcement steel f yk500 N/mm².
ØQ
74
124
155
185
260
345
450
490
585
645
705
805
L
ØR
12
12
16
16 10 60 635
16
r
n : Number of turns if the last one is welded else n + 1 if the last one is opened.
r : Number of reinforcement layers.
M
14
15
20
25
36
46
58
63
73
85
90
105
L = (Number of turns - 1) * P
Reinforcements shown on this form was placed in test specimens for load transfer tests (see § 3.6).
8
8
10
10
16
16
S
T
100
150
185
220
295
390
16 6 75 390 51
16 8 75 435
2
3
4
4
4
7
6
7
8
9
10
80
60
55
55
75
70
90
75
70
75
70
495
535
595
695
750
16 15 55 855

Annex 1 of the European Technical Approval No ETA-06/0006 33
ANCHORAGE TYPE CS
CATEGORIES OF USE ARRANGEMENTS

Annex 1 of the European Technical Approval No ETA-06/0006 34
ANCHORAGE TYPE CS
SIZES
Unit
6-7
6-12
6-19
6-27
6-31
ØA B C ØD E F1 ØF4 F2
222 60
258
360 110
390
80
300 90
122
136
149
170
203
217
143
178
210
256
274
6-37 420 130 236 300 82 805 149 925 136 211
F1: CS STANDARD length.
F2: CS PLUS and SUPER length.
ØH : Spacing of holes for fixation to formwork.
I : Thread hole.
: ØF4 for F2
50
60
70
69
69
225 80 360
392
660 139 810
620
95 530 81 117
540 110 660
ØF4
63
106
121
ØF3
85
148
181
149 740 136 188
G
80
90
100
100
100
110
ØH I
188 M12
220
260
310 M16
330
357
M12
M12
M16
M16

Annex 1 of the European Technical Approval No ETA-06/0006 35
ANCHORAGE TYPE CS
BURSTING REINFORCEMENT
6-7
6-12
6-19
6-27
6-31
12
16
6-37 20 9 65 645 30
16 12 50 695
Reinforcement steel f yk500 N/mm².
SPIRAL REINFORCEMENT
Unit ØN
P ØQ M L ØR
S T
16 5 65 345 30
16
Reinforcement for concrete with f cm(t) 28/35 N/mm² when stressing
n r
4 60
7 60
9 55
260
450
545
16 10 55 585 30
n : Number of turns if the last one is welded else n + 1 if the last one is opened.
r : Number of reinforcement layers .
Reinforcements shown on this form was placed in test specimens for load transfer tests (see § 3.6).
50
30
30
L = (Number of
turns - 1) * P
10
12
16
16
16
ORTHOGONAL REINF.
5
8
8
11
13
50 295
60
50 595
45
390
65 495
635

Annex 1 of the European Technical Approval No ETA-06/0006 36
ANCHORAGE TYPE H
SIZES AND BURSTING REINFORCEMENT
Anchorage sizeH6-4 L/2 As,min= 10 cm²/m L/2
6-3
6-4
6-7
6-12
6-19
6-22
6-31 810
6-37
Reinforcement for concrete with f cm(t) 28/35 N/mm² when stressing
Unit A B A B C D D1 ØE ØF ØG ØH
Arrangement 1 Arrangement 2
6-1 90 90 1 - - - - - 950 - - - 16/20
290
390
450
430
-
570
690
1050
90 3 -
90
230
-
230
230
260
370
210
90 4 230
-
390
470
-
-
-
-
190
210
-
330
390
- - 155 1600 1450 350
-
-
- - 950
-
155
155
155
165
175
-
1300
1300
-
1300
1900
2550
950
1150
1150
1150
1750
2400
-
-
200
230
300
400
400
-
- 70
16
16
16
16
20
20
64
83
114
140
146
171
178
21/25
28/32
28/32
28/32
6-15 450 230 9 370 370 9 155 1300 1150 300 16 130 28/32
10
12
28/32
28/32
6-27 690 260 17 - - - 155 1650 1500 350 16 171 28/32
14
18
Reinforcement steel f yk500 N/mm²
Number of Strand with lenght D1
4
8
-
- - - 490 470 20
1400 1250
- - - 530 510 20
1600 1450
-
-
-
-
-
-
570 510
690
510
-
4
5
-
12
16
-
20
-
24
L
1700 1550
2000
1850
Reinforcement as per
anchorage side
28/32
28/32

Annex 1 of the European Technical Approval No ETA-06/0006 38
COUPLER TYPE K
SIZES
Unit
6-3
6-7
430
6-4 440
560
6-12 660
6-19
160
160
160
200
210
310
160 400
6-22 910 160 610
6-31 970 180 625
6-37
A B C ØD ØE F ØG ØH
150
160
190
240
310
360
62
67
77
97 25
122
15
15
20
25
76
83
95
121
159
28/32
28/32
28/32
28/32
6-15 770 160 510 270 102 25 133 28/32
770 160 510 280 112 25 146 28/32
28/32
6-27 980 180 655 350 132 35 168 28/32
142 35 178 28/32
1200 200 830 400 155 35 203 28/32

Annex 1 of the European Technical Approval No ETA-06/0006 39
BLOCK OUT DIMENSIONS FOR ANCHORAGE TYPE E AND TYPE CS
CLEARANCE REQUIREMENTS
Unit Jack ZPE A B ØC D E ØF G
6-1 ZPE-30 135
53 600 100 140 1100
ZPE-23FJ 135 53 300 90 116 1200
6-2 ZPE-60 170
90 650 140 180 1100
6-3 ZPE-60 195 95 650 140 180 1100
6-4 ZPE-7A 220
110 800 200 280 1350
6-7 ZPE-12St2 305
135 670 200 310 1300
ZPE-200
1100 210 315 2100
6-12 ZPE-19 370
170 850 250 390 1500
6-19 ZPE-460/31 460
200 700 300 435 1500
ZPE-500
1150 330 550 2000
ZPE-500K
700 315 508 1500
6-22 ZPE-500 530
220 1150 330 550 2000
6-31 ZPE-750 595
260 1350 365 570 2300
ZPE-1000
1300 450 790 2200
6-37 ZPE-1000 640
270 1300 450 790 2200
ZPE-1250
1350 375 620 2250
6-43 ZPE-1000 680 250 1350 450 570 2300
ZPE-1250
1350 375 620 2250
6-55 ZPE-1000 760
255 1300 450 790 2200
ZPE-1250
1350 375 620 2250
Unit Jack ZPE A
6-7 ZPE-12St2
ZPE-200
360
6-12 ZPE-19 420
6-19 ZPE-460/31
ZPE-500
ZPE-500K
300
6-27 ZPE-750 520
6-31 ZPE-750 550
6-37 ZPE-1000
ZPE-1250
580
460 if ZPE-500K is used.
600 if ZPE-1250 is used.
According to the end zone arrangement
B
According to the end
zone arrangement
ØC D E ØF G
105 700 200 310 1300
1100 210 330 2100
130 850 250 390 1500
150 700 300 485 1500
1150 330 585 2000
700 315 508 1500
185 1350 365 570 2300
190 1350 365 570 2300
215 1300 450 790 2200
1350 375 620 2250

Annex 1 of the European Technical Approval No ETA-06/0006 40
DUCTING
Strand
No
Unit
Corrugated steel
strip sheath
Duct
VSL PT-PLUS
Smooth steel
duct
Plastic duct
for bare
Strand
Plastic duct
for Sheathed
Strand
Øint /Øext e Øint /Øext e Øext x t Øext x t min Øext x t min
1 6-1 25/30 5 23/25 4
2 6-2 40/45 9
3 6-3 40/45 6
4 6-4 45/50 7
5 6-7 50/57 8 58/63 13
6
55/62 9 58/63 11
7
55/62 7 58/63 9
8 6-12 65/72 11 76/81 18
9
65/72 9 76/81 16
10
70/77 11 76/81 15
11
70/77 9 76/81 13
12
75/82 11 76/81 12
13 6-15 80/87 13 100/106 25
14
80/87 11 100/106 24
15
80/87 10 100/106 23
16 6-19 85/92 12 100/106 22
17
85/92 11 100/106 20
18
90/97 13 100/106 19
19
90/97 12 100/106 18
20 6-22 100/107 17 100/106 17
21
100/107 16 100/106 16
22
100/107 15 100/106 15
23 6-27 100/107 14 115/121 22
24
100/107 13 115/121 22
25
110/117 18 115/121 21
26
110/117 17 115/121 21
27
110/117 16 115/121 20
28 6-31 110/117 15 130/136 27
29 120/127 21 130/136 27
30
120/127 20 130/136 26
31
120/127 19 130/136 25
32 6-37 120/127 18 130/136 24
33
120/127 17 130/136 23
34
120/127 16 130/136 22
35
130/137 22 130/136 22
36
130/137 21 130/136 21
37
130/137 20 130/136 20
38 6-43 140/147 25 150/157 31
39
140/147 24 150/157 30
40
140/147 23 150/157 9
41
140/147 23 150/157 29
42
140/147 22 150/157 28
43
140/147 21 150/157 27
44 6-55 150/157 27 150/157 27
45
150/157 27 150/157 27
46
150/157 26 150/157 26
47
150/157 25 150/157 25
48
150/157 24 150/157 24
49
150/157 23 150/157 23
50
160/167 29 150/157 24
51
160/167 28 150/157 23
52
160/167 27 150/157 22
53
160/167 27 150/157 22
54 160/167 27 150/157 22
55 160/167 26 150/157 21
Øext. of corrugations. Use next larger duct for strong deviation and long cables.
The corrugated steel strip sheaths of diameters larger than 130 mm follow the design of EN 523 with the same strip thickness.
Øext. of duct.
According to standard EN 10255, EN 10216-1, EN 10217-1, EN 10219-2 and EN 10305-3. Values given for information only. Design defines ducts.
According to standard EN 12201, material PE 80. Values given for information only. Design defines ducts.

Annex 2
TECHNICAL DATA
OF THE
VSL SLAB SYSTEM

Annex 2 of the European Technical Approval No ETA-06/0006 2
TABLE OF CONTENTS
Title Page
1. DEFINITION OF THE SYSTEM
1.1 PRINCIPLE OF THE VSL SLAB SYSTEM 4
1.2 CHARACTERISTICS OF SYSTEM UNITS 5
1.3 ANCHORAGES 5
1.3.1 PRESENTATION OF THE ANCHORAGES
1.3.2 LIST OF APPROVED ANCHORAGES
1.4 CATEGORIES OF USE, OPTIONS AND POSSIBILITIES 6
1.4.1 USES AND OPTIONS OF VSL SLAB SYSTEM UNITS
1.4.2 POSSIBILITIES OF THE VSL SLAB SYSTEM
2. STRANDS AND DUCTS
2.1 STRANDS USED 8
2.2 REQUIREMENTS OF THE UNBONDED SYSTEM 8
2.3 DUCTS USED FOR THE BONDED SYSTEM 8
2.3.1 TYPES AND DIMENSIONS OF USABLE DUCTS
2.3.2 METAL DUCTS
2.3.3 PLASTIC DUCTS
2.3.4 ACCESSORIES FOR INLETS, BLEED VENTS AND OUTLETS
2.3.5 CONNECTION WITH SLEEVES
2.4 CABLE LAYOUT 10
2.4.1 STRAIGHT LENGTHS BEHIND THE ANCHORAGES
2.4.2 RADIUS OF CURVATURE
2.4.3 SPACING OF THE SUPPORTS AND TOLERANCES
2.3.4 STRAND CUT LENGTH
2.5 INSTALLATION OF DUCTS AND TENDONS 11
2.6 PROVISIONAL PROTECTION AND LUBRICATION 11
2.7 CALCULATION ELEMENTS 12
2.7.1 FRICTION LOSSES
2.7.2 BASIS FOR EVALUATING ELONGATIONS
2.7.3 ACTIVE ANCHORAGE SETTINGS
3. ANCHORAGES
3.1 DESCRIPTION OF ANCHORAGE COMPONENTS 13
3.1.1 LIVE-END / DEAD-END ANCHORAGES
3.1.2 PRESENTATION AND PACKING OF ANCHORAGES
3.2 ORGANIZATION OF SUPPLY QUALITY 14
3.3 IMPLEMENTATION OF VARIOUS ANCHORAGES 14
3.3.1 TYPE "S 6-1" AND "S 6-4" LIVE-END ANCHORAGES
3.3.2 TYPE "S 6-1" AND "S 6-4" DEAD-END ANCHORAGES
3.3.3 TYPE "SF 6-1" EMBEDDED ANCHORAGES
3.3.4 TYPE "H 6-(1 through 4)" BONDED ANCHORAGES
3.4 ANCHORAGE ARRANGEMENTS 15
3.5 GEOMETRICAL AND MECHANICAL USE CONDITIONS 15
3.5.1 CLEARENCE BEHIND ANCHORAGES
3.5.2 CONCRETE COVER AND ANCHORAGE SPACING
3.6 BURSTING REINFORCEMENT 17
4. STRESSING
4.1 STRESSING EQUIPMENT 18
4.1.1 STRESSING JACKS
4.1.2 HYDRAULIC PUMPS
4.1.3 INSTRUMENTS AND MEASURING SYSTEMS

Annex 2 of the European Technical Approval No ETA-06/0006 3
4.2 PROCESSES OF STRESSING AND CONTROL PROCEDURE 19
4.2.1 FORCE MEASUREMENTS
4.2.2 ELONGATION MEASUREMENTS
5. INJECTION AND SEALING
5.1 INJECTION 20
5.1.1 UNBONDED SYSTEM
5.1.2 BONDED SYSTEM
5.2 SEALING 21
6. SCHEMATIC DRAWINGS 22

Annex 2 of the European Technical Approval No ETA-06/0006 4
CHAPTER 1
1. SYSTEM DEFINITION
DEFINITION OF THE SYSTEM
1.1 PRINCIPLE OF THE VSL SLAB SYSTEM
The cable or unit of the VSL Slab System is composed of one or several strands made of high-strength steel
called a "tendon", along with the associated set of anchorages.
In this system, the cable may be not only the unit itself, but also the assembly of several juxtaposed units (in
general of just one strand).
This System has considered two subsystems (to be called systems in the following discussion for the sake of
simplicity), i.e.:
- "unbonded", using individually greased and plastic sheathed monostrands placed directly in the
concrete. The unbonded protection of the tendons serves to make them independent of the structure.
Only greased sheathed monostrands will be considered in the ensuing discussion, see Section 2.1;
- "bonded", a grouting type of PT that uses bare strands. In this case, the strands are located within a
duct that constitutes a cylindrical or flat conduit. The void thus created is then filled with grout according
to EN 447 or Annex C4 of ETAG 013 for the purpose of bonding with the structure and inhibiting
corrosion.
The constituting strands are those defined in the European Standard White Draft pr EN 10138-3: "Prestressing
steels - Strand". They refer to 7-wire strands with nominal diameters of ∅ 15.2 and 15.7 mm (fpk = 1 860 N/mm 2
or fpk = 1 770 N/mm 2 ), which are identical to those used with the VSL Multistrand system.
As long as EN 10138 does not exist, 7-wire strands in accordance with national provisions shall be used.
By varying both the strand diameter and number (and, if applicable, their specified characteristic value of
maximum force), it would be possible to obtain a value for the characteristic tensile strength per cable or per unit
that varies between 260 and 1 116 kN.
Each strand, of a cable or unit, is individually stressed and becomes locked within a conical anchoring hole by
means of wedges.
The anchorage function is performed by clamping during strand moving back at the time of pressure release in
the jack.
The choice of post-tensioning units, as dictated by force requirements, leads for a given strand diameter and
characteristic strength to a specific number of strands to be laid out in accordance with a recommended spacing
plan. In conjunction with this design element, the choice of type of anchorage associated with the cable
depends on the intended function and application of the particular unit.
The system is limited to units of 1 and 4 strands since these units prove appropriate for common slabs and
plates.
The designation of post-tensioning units is expressed with reference to both the type and number of component
strands. The VSL commercial labeling is explained below:
The labeling of units 6-1… 6-4 or 6S-1… 6S-4 signifies:
the first digit indicates strand diameter,
6 = ∅ 6 × 1/10" = T15.2 ∅15.2 mm
6S = ∅ 6 × 1/10" S = T15.7 ∅15.7 mm (S stands for super).
the subsequent digits indicate the number of strands composing the unit.
To provide greater detail, the designation of units begins with the names of the anchorages placed at the ends.
The following designation serves as an example:
Cable VSL S-S 6S-4 L = 50.000 (2)
Cable VSL 4(S-S 6S-1) L = 50.000 (2) [juxtaposition lying flat generally composed of 4 monostrand units]
The functions and names of the anchorages will be defined hereafter. The cables feature a length of 50.000 m
and have been stressed at both (2) ends.
The VSL Slab System contains 1 and 4 strand units. The intermediately-dimensioned cables of 2 and 3 strands
are composed preferentially by means of juxtaposing several monostrand units.
The prestressing force applied may naturally be fine-tuned to meet the required prestressing force level by
adjusting the appropriate spacing between units.

Annex 2 of the European Technical Approval No ETA-06/0006 5
1.2 CHARACTERISTICS OF SYSTEM UNITS
On the basis of the strand characteristics defined in draft Standard "pr EN 10138-3: Prestressing steels - Part 3:
Strand", the values of tendon cross-sections Ap, maximum forces under anchorage upon tensioning recom-
mended by EC2 : Pmax = min {k1.Ap.fpk; k2.Ap.fp0.1k}, with k1 = 0.8, k2 = 0.9, fpk = 1 860 N/mm 2 , fp0.1k = 0.88 fpk, of
VSL post-tensioning units are as follows :
Number of
strands in the
prestressing
unit
Ap
STRAND ∅ 15.2 - T15.2 or 6
fpk = 1 860 N/mm 2
Fpk = 260 kN Fp0.1k = 229 kN
Ap.fpk
0.8
Ap.fpk
Ap.fp0.1k
0.9
Ap.fp0.1k
Ap
STRAND ∅ 15.7 - T15.7 or 6S
fpk = 1 860 N/mm 2
Fpk = 279 kN Fp0.1k = 246 kN
Ap.fpk
0.8
Ap.fpk
Ap.fp0.1k
0.9
Ap.fp0.1k
mm² kN kN kN kN mm² kN kN kN kN
1 140 260.0 208.0 229.0 206.1 150 279.0 223.2 246.0 221.4
2 280 520.0 416.0 458.0 412.2 300 558.0 446.4 492.0 442.8
3 420 780.0 624.0 687.0 618.3 450 837.0 669.6 738.0 664.2
4 560 1 040.0 832.0 916.0 824.4 600 1 116.0 892.8 984.0 885.6
Note : prestressing force applied to structure must be in accordance with national regulations
The system can obviously be used with strands displaying a specific characteristic tensile strength of less than
that proposed in the table as strands with fpk = 1 770 N/mm 2 . The provisions for tendons with strands with a
characteristic tensile strength fpk = 1 860 N/mm 2 also apply to tendons with strands with fpk < 1 860 N/mm 2 .
The draft Standard pr EN 10138-3 sets the following criteria for the other useful characteristics of prestressing
strands composing the VSL units:
- Elongation at maximal force: ≥ 3.5%
- Relaxation at 0.70 fpk after 1,000 hours: ≤ 2.5%
- Relaxation at 0.80 fpk after 1,000 hours: ≤ 4.5%
- Fatigue behaviour (0.70 fpk; 190 N/mm 2 ): ≥ 2x10 6 cycles
- Maximum D value of deflected tensile test: ≤ 28%
- Modulus of elasticity Ep: 195 000 N/mm 2
The strands are stressed individually, the modulus of elasticity of the strand measured and communicated at the
time of its supply is to be taken into account for the cable elongation calculations.
Individually greased and sheathed monostrands have the same mechanical properties as listed above for bare
strands.
1.3.1 PRESENTATION OF THE ANCHORAGES
1.3 ANCHORAGES
The VSL Slab System anchorages are all (with the exception of the type "H" bonded anchorages) available for
the two systems of unbonded or bonded tendons. Depending on their function and commercial labeling, the
anchorages may be classified as follows:
Type "S 6-1" and "S 6-4" live end anchorages
These active anchorages have been designed to anchor tendons at the end at which the stressing will be
performed strand by strand.
They are composed of a single-block anchorage casing drilled with conically-shaped holes (1 or 4) in which the
strands are anchored by means of locking through the use of wedges. These anchorages exist in both the
unbonded and bonded systems.
The continuity of protection and the waterproof sealing between the duct and the anchorage casing are provided
by means of a plastic sleeve.
In the unbonded case, a cap is required to close the housing of the wedges after filling with a protective product
(identical or compatible with that of the greased and sheathed single strands) by injection.
The "S 6-1" anchorage can be used as an intermediate anchorage at a construction joint with the strand being
continuous through the anchorage and over the entire tendon length to the end anchorage. The tendon is first
stressed at the intermediate anchorage at the construction joint. When the entire slab is built, the tendon is
stressed at the end anchorage and the intermediate anchorage becomes obsolete but remains in place.

Annex 2 of the European Technical Approval No ETA-06/0006 6
Type "S 6-1" and "S 6-4" dead end anchorages
These passive anchorages ensure the locking of tendons at the end on which no stressing force is being
exerted by means of the jack. These anchorages apply to both the unbonded and bonded systems.
This category only includes those anchorages that remain accessible at the time of stressing.
The type "S" anchorages, whose wedges have been pre-locked and which may be controlled during stressing
are used for the given function.
The protection of these dead end anchorages is identical to that of the live end anchorages.
Type "SF 6-1" embedded dead end anchorages
These fixed anchorages are incorporated into the concrete of the structure. Only considered as embedded
anchorages are those that make use of a direct transfer on the concrete in order to lock the tendon ends.
In both the unbonded and bonded systems, the type SF 6-1 anchorages, which have been assembled onto the
tendons prior to their installation, are used for the given function. Their wedges are locked into the anchorage
body S 6-1 and maintained using a series of washers and springs supported on the caps screwed at the end, a
set-up that provides mechanical protection against any slipping movement. The SF 6-1 anchorages receive the
same protection as the S 6-1 anchorages.
Type "H 6- (1 through 4)" bonded anchorages
These fixed anchorages rely, at least in part, on bonding in order to maintain the tendon end fastened with
respect to the concrete. They are strictly the same as those of the VSL Multistrand System, which has been
detailed in Annex 1.
These anchorages may only be used for the bonded system.
1.3.2 LIST OF APPROVED ANCHORAGES
The set of approved anchorages that allow creating all of the intermediate prestressing units have been
categorized in the following table:
System
unbonded
bonded
ANCHORAGES
Functions Live end Dead end Embedded
Dead end Bonded
Unit Commercial label S S SF
1T15 / 1T16 6-1 / 6S-1
4 6-4 / 6S-4
CABLES
Unit Commercial label Si Si SFi H
1T15 / 1T16 6-1 / 6S-1
4 6-4 / 6S-4
The stressing of tendons anchorages is only conducted by VSL stressing jacks, which are presented in Chap. 4.
1.4 CATEGORIES OF USE, OPTIONS AND POSSIBILITIES
1.4.1 USES AND OPTIONS OF VSL SLAB SYSTEM UNITS
The VSL Slab System units are entirely internal to the concrete; they may be:
- either unbonded, i.e. with individually greased and sheathed monostrands, unbonded to the structure,
- or bonded, i.e. with "bare" strands placed inside a duct and with permanent grouting, providing bonding
to the structure.
These units may also be:
- replaceable provided the absence of bonding with the structure,
- designed to be encapsulated and perfectly waterproof,
- designed to be electrically-isolated.

Annex 2 of the European Technical Approval No ETA-06/0006 7
Anchorages S SF Si SFi S Si H
Uses
6-1 6-1 6-1 6-1 6-4 6-4 6-1:6-4
internal* bonded cable with metallic
duct
internal* bonded cable with plastic duct
internal* unbonded
external* bonded cable
external* unbonded cable
tendon for use in various material as
external cable (1)
restressable tendon
exchangeable tendon (2)
encapsulated tendon (leak tight)
electrically isolated tendon
(*) of concrete
It goes without saying that the solutions and options implemented presume the availability of adequate choices
and combinations of all unit or cable components, as indicated in this ETA:
- for strands see Chapter 2.1 "Strands used",
- for ducts see Chapters 2.2 "Requirements of the unbonded system" and 2.3 "Ducts used for bonded
system",
- for anchorages see Chapter 3.4 "Anchorage arrangements",
- for injection see Chapter 5.1 "Injection".
(1) the anchorage must be embedded in concrete block.
(2) the designer must check feasibility regarding geometrical tendon layout.
1.4.2 POSSIBILITIES OF THE VSL SLAB SYSTEM
The VSL Slab System is able to take advantage of the following unique set of possibilities:
- Partial stressing or stressing in stages:
When prestressing needs to be applied gradually, the stressing may be performed in stages. With the first
partial stressing step being carried out at the beginning of the second stage, the wedges are unclamped by
action of the jack on the strand. Once the targeted force has been reached, pressure in the jack is relaxed
and the wedges are once again locked inside the anchorage. This procedure consists of the same steps as
for stressing a long cable strand whose elongation necessitates several successive jack strokes.
Since the strands have been stressed individually, the procedure may also entail the total stressing of a
fraction of the strands.
- Destressing procedure:
The destressing of a strand(s) anchored by a type "S 6-1" or "S 6-4" anchorage is possible using a special
tooling assembly mounted on the stressing jack provided that the required strand over lengths have been
conserved and that the strands remain independent of the structure (unbonded).
From the aforementioned, two zones appear to stand out, the current zone and the anchorage zone; they will be
presented in greater detail in the following chapters entitled "Strands and ducts" and "Anchorages".

Annex 2 of the European Technical Approval No ETA-06/0006 8
CHAPTER 2
STRANDS AND DUCTS
2. TENDONS AND DUCTS
2.1 STRANDS USED
The high-strength prestressing steel (strands) composing the tendons are labeled "Y1860S7 – No. 1.1366" and
are defined in the draft Standard "pr EN 10138-3: Prestressing steels – Part 3: Strand". On an occasional basis,
the strands labeled "Y1770S7 – No. 1.1365" may also be employed.
The primary characteristics have been recalled in Section 1.2.
As regards monostrands (individually greased and sheathed) that are used in the unbonded system, they are
compliant with Annex C.1 of the ETAG 013, which specifies the requirements, verification methods and
acceptance criteria of both the grease and the sheathing.
2.2 REQUIREMENTS OF THE UNBONDED SYSTEM
While it is obvious that the individually greased and sheathed monostrand do not necessitate any duct, the
cables composed by juxtaposing side by side several monostrands however require assembly by means of
regularly-spaced spacers ensuring their respective positions / linear lay out within the group.
The connection of the monostrand sheathing with the anchorage is conducted by means of inserting the strands
in a sleeve with one inlet for the "S 6-1" anchorage or a sleeve with 4 inlets for the "S 6-4" anchorage. These
connections are made of plastic and provide for a watertight seal with the sheathing.
2.3 DUCTS USED FOR THE BONDED SYSTEM
The VSL Slab System can use several types of duct as provided in this section. Duct type selection depends on
the specific project, the final use designed for the structure and the options selected for the post-tensioning
units.
Although the VSL Slab System authorizes the use of cylindrical ducts, the applications targeted with the slabs
and plates increasingly rely upon the flat ducts presented below. For cylindrical ducts, the interested reader is
advised to consult Annex 1 of this ETA.
2.3.1 TYPES AND DIMENSIONS OF USABLE DUCTS
Depending on the specific application, various types of ducts may be employed. From a general standpoint, the
ducts used must be mechanically resistant, display continuity in shape, ensure continuity of the seal over their
entire length and comply with the project's bond requirements, while not causing any chemical attack.
Without claiming to be exhaustive, the frequently-used ducts of the following table have demonstrated their
capacities in the uses and applications cited:
Ducts
Metal duct Plastic duct
Applications Corrugated steel strip flat sheath VSL PT-PLUS ® flat duct
Cable with standard ~
inside the
concrete
bonded
injection
encapsulated
electrically
isolated
×
×
ª
ª
Note ª: This set-up features a fully-bonded cable.
: Advised ~ : Possible × : Unadvised or forbidden

Annex 2 of the European Technical Approval No ETA-06/0006 9
The VSL Slab System's prestressing tendon ducts, with either a cylindrical cross-section or oblong, must display
internal dimensions large enough to provide for easy tendon installation and adequate filling during grouting of
the protective product.
The small internal dimension of the oblong section is considerably less than two strand diameters in order to
ensure that they remain juxtaposed side by side, in the same position all along the tendon.
The most common duct sizes are listed on drawing "Ducting" of Chapter 6.
2.3.2 METAL DUCTS
Tendons are most often isolated from the concrete by means of corrugated steel strip cylindrical or flat sheaths.
Although not covered in Standard EN 523, these flat sheaths due to their shapes and dimensions may be
qualified as normal (Category 1). Their characteristics are nearly the same as those of the cylindrical sleeve
stipulated in the standard.
Connections between coils or straight segments are performed by means of a coupler on the two extremities to
be connected. The waterproof sealing at the joints is provided by either an adhesive ribbon or thermoretractable
sleeves.
2.3.3 PLASTIC DUCTS
In the case of stringent requirements as regards to both corrosion protection and fatigue resistance of cables, it
is recommended to use the corrugated plastic VSL PT-PLUS ® flat (or cylindrical) duct; this material generates
perfect bonding between the tendons and the structure. It is the preferred choice for tendons submitted to a
particularly-aggressive environment or strong fatigue loads. The fittings between ducts segments are introduced
by means of connectors that serve to generate a waterproof sealing. The VSL PT-PLUS ® duct complies with
ETAG 013.
The VSL PT-PLUS ® duct with its set of appropriate fittings is also employed in the case of fully-encapsulated
(waterproof) and or electrically isolated cables. This application necessitates the presence of rigid half-shells
between the duct and its supports at all the high points along the cable path in order to avoid any risk of
perforation during stressing of the tendon.
2.3.4 ACCESSORIES FOR INLETS, BLEED VENTS AND OUTLET
Providing permanent protection by means of grout injection presupposes the possibility of intervening anywhere
along the cable path in order to adjust the filling and bleed any air, water, etc. that may be within the ducts. In
this aim, accessories for inlets, venting and outlets are installed on the ducts. These basically comprise shells or
collars fastened onto holes in the ducts and then connected to pipes with plugs opening onto the slab surface or
subsurface.
Duct Duct connection accessory Inlet, venting, bleeding or outlet
accessory
Corrugated steel strip sheath Sealed plastic shell Plastic pipe
VSL PT-PLUS ® duct Special "clipped" collar Plastic pipe
The distributions of inlet, venting, bleeding and outlet points along the cable profile are selected based on a
function-specific study of the cable path.
2.3.5 CONNECTION WITH SLEEVES
The strands, placed within their ducts, must slightly dilate in the vicinity of the "S 6-4" anchorages in order to
pass through the corresponding holes in the anchorage body. This "variable oblong"-shaped duct expansion is
called a trumpet and is considered part of the anchorage element.
The trumpets are fastened to the formwork of appropriate dimensions, with enough length and opening at the
end to allow for connection and alignment of the duct of the current zone.
The sealing between the ends of duct and trumpet is carried out using an adhesive strip, a thermo-retractable
sleeve, or a connector designed as a duct accessory (e.g. a VSL PT-PLUS ® coupler).

Annex 2 of the European Technical Approval No ETA-06/0006 10
2.4 CABLE LAYOUT
The cable layout patterns are not inherent to the VSL Slab System, but instead depend on the particular project.
2.4.1 STRAIGHT LENGTHS BEHIND THE ANCHORAGES
In order for the strands not to display excessive deviation with respect to the anchorage support surface, it is
recommended to lay out a rectilinear segment in the back of the anchorage. In both systems (unbonded and
bonded), whether the systems include an individual sleeve and a shared sleeve, their trumpet length is sufficient
as straight length needed behind the anchorage.
2.4.2 RADIUS OF CURVATURE
- unbonded system:
The individually greased and sheathed monostrands typically laid out either isolated or flat juxtaposed must
satisfy the minimum radius of curvature rmin :
deviation : rmin ≥ 2.50 m,
loop anchorage: rmin ≥ 0.60 m, the term loop anchorage indicates a zone with strong curvature
over which the total deviation is nearly π radians and which is located at approximately mid-length of the
cable, with simultaneous stressing at both ends.
In the case of an anchorage with several strands, the strands are to be laid out such that the radial force due to
deviation of one strand does not harm the adjacent strand.
- bonded system:
The corrugated steel strip flat sheath is bent by respecting a minimum radius of curvature rmin. With the sheath
laid out flat (see drawing "Ducting" of Chapter 6), the following dimensions are respected:
plane: rmin ≥ 6.00 m,
elevation: rmin ≥ 2.50 m.
The VSL PT-PLUS ® flat duct is bent by respecting a minimum radius of curvature rmin. With the duct laid out flat,
the following dimensions are respected:
plane: rmin ≥ 6.00 m,
elevation: rmin ≥ 2.50 m.
2.4.3 SPACING OF THE SUPPORTS AND TOLERANCES
The support heights underneath the cables or ducts are listed on the cable diagrams approximately every meter
for a large radius of curvature and every fifty centimeters for a small radius of curvature, in order to allow for
cable (or duct) placement with the required level of precision.
The cable (or duct) supports are laid out as stipulated in the design that also establishes the order in which the
cables (or ducts) are to be installed to ensure installation without "intertwining" in the case of slabs with tendons
in both directions.
The fastening fittings are sufficiently robust and close enough such that the cables (or ducts) will not exhibit
displacements or deformations in excess of the allowed tolerances.
The tolerances on cable positions in the concrete elements must respect the prescriptions stipulated in draft
standard "pr ENV 13670-1".
Moreover, in every direction, whenever a cable displays or potentially displays deviation in the vicinity of an
edge of concrete which could lead to spalling of the concrete cover, an offset with respect to the cable diagram
in this direction is only tolerated provided that equilibrium reinforcing bars are provided over this zone. Special
attention must be paid to outward pressure due to structural singularities, such as floor openings.
The VSL Slab System authorizes the cable installation technique according to the so-called "free path" or "freie
Spanngliedlage" method defined here after.
- In slabs with a thickness of not more than 450 mm the tendons can be placed with the method of “Freie
Spanngliedlage”.
- Tendons placed with the method of “Freie Spanngliedlage” need only a limited number of tendon supports, in
general at the low and high points of the tendon profile, however, with limitations on the spacing as stated
below.
- The maximum spacing of tendon supports is:

Annex 2 of the European Technical Approval No ETA-06/0006 11
- 1.5 m between the tendon fixation to the top layers of reinforcement and an adjacent anchorage,
- 3.0 m between the tendon fixation to the bottom layers of reinforcement and an adjacent anchorage or
the tendon fixation to the top layer of reinforcement.
- At the low points and high points of the tendon profile, the tendons have to be fixed to the top and bottom
layers of reinforcement, respectively, on least two locations which have a distance of between 0.3 to 1.0 m. The
fixation shall ensure a tight fit without damaging the tendon sheathing. The reinforcement layers have to be fixed
in accordance with the relevant standards.
2.4.4 STRAND CUT LENGTH
Since the anchorage has been fastened with respect to the part undergoing post-tensioning, its space
consumption is limited to its specific volume. Strand length is strictly the length of the prestressed element
between the anchorages increased by the over length crossing the stressing jack(s).
These over length have been defined in the drawing "Clearance requirements" of Chapter 6.
2.5 INSTALLATION OF DUCTS AND STRANDS
Depending on the size and layout of the worksite, the available space on site and the schedule of works, one of
the following solutions is to be adopted:
- unbonded system:
- cables fabricated in the plant and then delivered as needed to the worksite for installation into the
passive reinforcement;
- cables fabricated in a mobile workshop on the worksite, all ready to be installed in the passive
reinforcement.
- bonded system:
- cables (both tendons and ducts) fabricated in the plant and then delivered as needed on the
worksite for installation into the passive reinforcement;
- strand bundle fabricated in a mobile workshop located adjacent to the worksite and then drawn
before concreting into the ducts installed in the passive reinforcement;
- tendons composed by threading strand by strand before concreting into the ducts installed in the
passive reinforcement.
Note: If round ducts are used, threading of strand may also be done after concreting.
2.6 PROVISIONAL PROTECTION AND LUBRIFICATION
In the bonded system, the oiling or greasing of tendons, exclusively by means of non-dangerous substances, is
performed:
- in the aim of providing provisional protection against corrosion from the time of leaving the plant until
permanent protection has been achieved (grouting of the cable);
- in the aim of lubrication since the friction loss of oiled strands in the metal ducts during stressing is lower.
With this same objective, other products serving to reduce friction may be used, as long as they are recognized
as non-dangerous, can be easily applied and remain inert in the presence of permanent protection (and the
eventual rigid bond to the structure)..
It is necessary to point out that:
"In addition to the specific clauses relating to dangerous substances contained in this European Technical
Approval, there may be other requirements applicable to the products falling within its scope (e.g. transposed
European legislation and national laws, regulations and administrative provisions). In order to meet the
provisions of the EU Construction Products Directive, these requirements need also to be complied with, when
and where they apply."

Annex 2 of the European Technical Approval No ETA-06/0006 12
2.7.1 FRICTION LOSSES
2.7 CALCULATION ELEMENTS
The friction of strands in their ducts, which hinders tendon displacement during stressing, causes a tensile loss
by friction all along the cable path beginning at the considered live-end anchorage.
In examining the friction loss formula: f po (x) = f po (0) . e
- μ ( θ + k x ) , which expresses the tension in a
cable at the abscissa x as a function of the tension at the considered live end anchorage (positioned at x = 0),
where μ is the coefficient of friction (over the curve) between the strands and the duct, θ the sum of the
angular deviations of the cable over the distance x, and k the unintentional angular deviation (per unit length)
affecting the cable path,
it is recommended to adopt the numerical values of μ and k prescribed in Eurocode 2 which can be summarized
as follows:
Application μ (rad -1 ) k (rad/m)
Individually greased and sheathed monostrand 0.05 0.020 - 0.060
Cable with corrugated steel strip sheath 0.17 - 0.19 0.005 - 0.010
Cable with VSL PT-PLUS ® duct 0.12 - 0.14 0.005 - 0.010
The interval limit values encompass both lubricated and non-lubricated strands.
2.7.2 BASIS FOR EVALUATING ELONGATIONS
See Section 2.6.2 of Annex 1.
On the worksite during stressing, whether the unbonded or bonded system is being employed, elongation only
gets evaluated once the strand has been stiffened inside its duct.
Note : friction losses at anchorages are expressed in Chapter 4.2.1.
2.7.3 ACTIVE ANCHORAGE SETTINGS
The following wedge draw-in values will be applied herein:
- 6 mm, which remains constant for all units and is applicable to all types of anchorage using the
"6N" or "6S" wedges implemented without activation of the seating ram of the stressing jack (see
Section 4.1.1).
- 5 mm, which remains constant for all units and applicable to all types of anchorage using the "6N"
or "6S" wedges implemented with activation of the seating ram of the stressing jack (see
Section 4.1.1).
The VSL Slab System anchorages do not allow for any adjustment with shim.

Annex 2 of the European Technical Approval No ETA-06/0006 13
3. CHAPTER ANCHORAGES 3
3.1 DESCRIPTION OF ANCHORAGE COMPONENTS
VSL Slab System anchorages make use of a set of standard elements that can be categorized as follows:
3.1.1 LIVE END / DEAD END ANCHORAGES
ANCHORAGES
For these active/passive anchorages, the anchor head and plate are combined to form a single part, commonly
called the anchorage body.
These anchorages comprise:
- S 6-1 anchorage
The anchorage body is molded and cast in cast iron with spheroidal graphite in accordance with Standard
EN 1563; the conically-shaped hole, subject of a rigorous control, is drilled into this body. The cast iron used
herein is EN-GJS-500-7.
The plastic sleeve is screwed onto the anchorage body.
In the unbonded case, the end cap is made of plastic material.
In the bonded case, a temporary or permanent cap provides for the waterproof seal of the envelope at the
anchorage end in order to perform the grouting.
- S 6-4 anchorage
The anchorage body is molded and cast in cast iron with spheroidal graphite in accordance with Standard
EN 1563; the four conically-shaped holes are drilled into this casing and rigorously controlled individually. The
cast iron used herein is EN-GJS-500-7.
The plastic sleeve of this anchorage is inserted into the concrete and accommodates in an appropriate form the
simply-supported anchorage body.
In the unbonded case, a permanent cap filled with grease protects the end anchorage.
In the bonded case, a provisional or permanent cap provides a waterproof sealing of the envelope at the
anchorage end in order to perform the grouting.
- Wedges
The wedges used for both the VSL Slab System and VSL Multistrand System are identical (see Annex 1).
3.1.2 PRESENTATION AND PACKING OF ANCHORAGES
The unbonded system:
Since the installation of the monostrands and anchorage body for the S 6-1 anchorage or the trumpet for the
S 6-4 anchorage is done prior to concreting, the delivery of anchorages to the worksite entails:
1. Delivery of the S 6-1 anchorages or the S 6-4 trumpets, along with the monostrand coils and the
installation accessories for both cable manufacturing and placement in the passive reinforcement.
These anchorage components are fixed to the formwork. The anchorage components are delivered
already tagged, packaged and protected.
After concreting and cure of the concrete,
2. Delivery of the wedges, eventually along with installation of the S 6-4 anchorage units, the stressing
operation, cutting of the strand over lengths and permanent protection of the anchorages. These
anchorage components are delivered identified, packaged and protected.
The bonded system:
Given that strand placement takes place before concreting, the delivery of anchorages on the worksite entails:
(only the most common case of internal (concrete) post-tensioning of a new structure will be highlighted herein)
1. Delivery of the S 6-1 anchorages or the S 6-4 trumpets, the ducts, the accessories for placement within
the passive reinforcement, along with the strands to be threaded. These anchorage parts are fastened
to the formwork. The anchorage units come delivered tagged, packaged and protected.

Annex 2 of the European Technical Approval No ETA-06/0006 14
Following concreting and curing of the concrete,
2. Delivery of the wedges (eventually the S 6-4 anchorage body), the stressing operation, cutting of the
excess lengths and grouting for the permanent protection of both cables and anchorages. These
anchorage components are delivered identified, packaged and protected.
3.2 ORGANIZATION OF SUPPLY QUALITY
The fabrication of anchorage components of the post-tensioning system and especially those designed for the
VSL Slab System is conducted in compliance with the specifications, production and control procedures laid out
in the present ETA document and all associated documents.
The control procedures in effect for anchorage Component Manufacturers, to the same extent as those adopted
by the PT Specialist Company, serve to ensure the traceability of the components all the way through to their
delivery on site. It is to be recalled that the basis for evaluating these procedures and the supervision of their
application have been defined in Chapter 8 and its Appendix E of the ETAG 013.
It should also be recalled that prior to installation, the compliance of all delivered components, by means of both
identification and visual inspection of their state, must be performed by the PT Supervisor.
3.3 IMPLEMENTATION OF VARIOUS ANCHORAGES
The implementation of VSL units must be assigned to a competent staff member and involve technical
management personnel within the PT Specialist Company or a PT Supervisor certified by this company.
3.3.1 TYPE "S 6-1" AND "S 6-4" LIVE END ANCHORAGES
The S 6-1 anchorage bodies and the S 6-4 trumpets are fixed to the formwork and connected to the
monostrands or ducts aligned at the time of their installation, in general during placing of the passive
reinforcement, then incorporated therefore to the structure or structural element during concreting.
Depending on the type of system (bonded or unbonded), sleeves or trumpets are appropriate.
For detail of connections of anchorages with current ducts refer to Chapter 2.2: “Requirements of the unbonded
system” and 2.3: “Duct used for the bonded system”.
The S 6-1 anchorage, used like an intermediate anchorage, is strictly installed as a live end anchorage with the
tendon that crosses it coiled up and stored beyond. After stressing of the first-phase length during installation of
the second-phase tendon and duct, a sleeve is laid out in order to link the anchorage and this duct.
The S 6-4 anchorage unit is installed into the trumpet which was placed before concrete pouring. The wedges
are placed immediately prior to stressing, which ensures that they are clean for use.
For force losses in the anchorages during stressing, see Section 4.2.1: "Force measurements".
3.3.2 TYPE "S 6-1" AND "S 6-4" DEAD END ANCHORAGES
The placement of these passive anchorages is performed as indicated in Section 3.3.1. Once the anchorage
has been installed, before stressing at the other end, the wedges are pre-locked using a wedge tool. The
anchorage then remains accessible throughout the stressing phase for observation.
3.3.3 TYPE "SF 6-1" EMBEDDED ANCHORAGES
In both the bonded and unbonded systems, the fixed SF6-1 anchorages are assembled on the strands, then
the wedges are pre-locked and verified and, lastly, the ducts and sleeves are connected. The anchorages
assembled in this manner are then positioned and inserted into the passive reinforcement.

Annex 2 of the European Technical Approval No ETA-06/0006 15
3.3.4 TYPE "H 6- (1 through 4)" BONDED ANCHORAGES
These fixed anchorages reserved for the bonded system are strictly identical to those of the multistrand system
described in Annex 1.
3.4 ANCHORAGE ARRANGEMENTS
According to categories of use, referring to Section 1.4.1, arrangements of anchorage components are descri-
bed in the following table :
Anchorages
Components
Uses
S and Si 6-1
Anchorage
Unit
SF and SFi
6-1
Anchorage
Unit
Anchor
Body
S and Si 6-4
Sleeve Cap
internal bonded cable with
metal duct
S S S Si S
internal bonded
plastic duct
cable with
S S S Si S
internal unbonded S S S S S
exchangeable tendon S S S S
encapsulated tendon (leak tight) S S S S Si S
electrically isolated tendon S (1) S Si S P (2)
Notes : 1 : Electrical isolation provided by plastic trumpet (anchor body),
2 : Plastic cap,
3.5 GEOMETRICAL AND MECHANICAL USE CONDITIONS
For the seating and installation of anchorages, certain construction-related conditions must be verified.
3.5.1 CLEARANCES BEHIND ANCHORAGES
In order to facilitate jack placement and simplify the stressing procedure, a free space must be allocated behind
the anchorage.
These dimensions are given in the drawing Page 29 "Clearance requirements" in Chapter 6.
3.5.2 CONCRETE COVER AND ANCHORAGE SPACING
Introducing post-tensioning forces into the structures takes the form, within the anchorage zones, of
concentrated forces applied onto the anchorage bodies. The high stress values encountered underneath the
anchorages necessitate certain construction-related measures, i.e.:
- The anchorages must be laid out at a sufficient distance from the nearest edge of the concrete (cover) and
respect a spacing between anchorages (centre to centre) that will be specified below.
- The concrete in the vicinity of the anchorages must be especially homogeneous and display, at the time of
stressing, an adequate level of strength.
- A general diffusion zone must be designed and prepared in front of the anchorages within the structure,
thereby reducing the concentrated forces and distributing them over the concrete cross-section, in
compliance with the design rules.
As stated above and in considering a maximum prestressing force P(t,x) at the time of stressing (t = 0) at the
anchorage (x = 0), thus called P(0,0) ≤ Pmax, for the normal anchor plates and P(0,0) max = Pmax, the following are
defined:
Force in the cable, at the anchorage on the concrete side, before load transfer to anchorage.

Annex 2 of the European Technical Approval No ETA-06/0006 16
b0 and b’0 are the distances between the anchorage axis and the edge of the block tested. These values are
given in the tables here after.
The reinforcement required to prevent bursting and spalling in anchorage zones is determined in relation to a
rectangular prism of concrete, known as the primary regularisation prism, located behind each anchorage. The
cross section of the prism associated with each anchorage is known as the impact rectangle.
The impact rectangle has the same centre and the same axes of symmetry as the anchor plate (which should
have two axes of symmetry).
The impact rectangle with dimensions c x c’ has the same area as the block tested A = 4 x b0 b’0 and the same
aspect ratio (variation of -15% is allowed in one direction).
cmin,rect = 0.85 x 2 b0 ; c’ min,rect = 0.85 x 2 b’0
cmin and c’min taking into account dimensions of bursting reinforcement are given in the tables here after, then
c ≥ cmin or c’ ≥ c’min (1)
and c x c’ = A = 4 x b0 b’0 (2)
Rules for center distance and edge distances of anchorages:
Impact rectangles associated with anchorages located in the same cross section should not overlap.
In addition, they should remain inside the concrete. Taking into account the concrete cover, we obtain the
distance to edge in the two directions :
c
c '
+ cov er − 10mm
and
+ cov er − 10mm
2
2
Note: 10 mm is the concrete cover in the tested block.
For anchorage spacing, refer to equations (1) and (2)
For f cm(t) ≥ 16/20 N/mm 2
Anchorage S 6-1 S 6-4
u | u’ mm (1) 105 75 280 115
2b0 | 2b’0 mm (2) 180 120 400 220
cmin | c’min mm
155 100 340 185
(1) Sizes of anchor plate / anchorage body
(2) Sizes of test block
During cable stressing, the concrete in front of the anchorages must have reached an adequate strength level,
i.e. a 100% stressing of P(o,o) max = Pmax is not permitted if fcm(t) < 16/20 N/mm 2 , regardless of the anchorage
layout within the concrete element.
It remains possible however to partially tension the tendon.
In the case of stressing to 50% of the maximum value at the anchorage for example, the characteristic
strengths fcm(t) may be reduced to approximately 2/3 of the values indicated above for total stressing.
It is to be recalled that for those anchorages relying upon bonding alone, i.e. for type "H" anchorages, concrete
strength within the anchorage zone during stressing must be: fcm(t) ≥ 28/35 N/mm 2 .
b 0
b’0

Annex 2 of the European Technical Approval No ETA-06/0006 17
3.6 BURSTING REINFORCEMENT
A bursting reinforcement is required in the local anchorage zone due to application of the concentrated posttensioning
force.
In all cases, the general anchorage zone must contain a reinforcement for equilibrium designed by the project
designer in accordance with typical design rules (see examples presented in the drawing Page 27
"Reinforcement of anchorage zones" in Chapter 6).
As foreseen by this ETA, the local zone reinforcement specified in this ETA and confirmed in the load transfer
tests, may be modified for a specific project design if required in accordance with national regulations and
relevant approval of the local authority and of the ETA holder to provide equivalent performance.
The contractor responsible for concreting must ensure that the density and configuration of reinforcement within
the diffusion zone allow for adequate and homogeneous concreting of the entire zone.

Annex 2 of the European Technical Approval No ETA-06/0006 18
CHAPTER 4
4. STRESSING
4.1 STRESSING EQUIPMENT
The VSL equipment used for stressing is primarily composed of stressing jacks, hydraulic power packs
(commonly called pumps) and the associated set of measurement instruments or systems.
4.1.1 STRESSING JACKS
The strands are individually stressed by means of VSL stressing jacks, which are available according to two
types:
- a double acting front-gripping hollow piston jack,
- a twin ram double acting jack, with solid pistons laid out on both sides of the strand. This configuration allows
for stressing the intermediate anchorages.
This equipment enables stressing the strand in one or several stages and then, if need be, to de-stress the
strand. Their primary characteristics will be defined below.
In sequence starting from the anchorage, these jacks are composed of:
- 1 nose (chair ring) at the front resting upon the anchorage body, ultimately associated with a seating ram;
- 1 body or cylinder, composed of one or two jacks and resting upon the chair ring,
- 1 auxiliary anchorage driven by the piston(s) and laid out as close as possible to the anchorage installed in
place in order to limit the over length of the strands. The ungripping of the jack anchorage is performed
automatically.
List of VSL jacks:
Designation DKP 6 ZPE 23 FJ
Type 2 // pistons 1 hollow piston
Cross section mm 2
240 x 165 ∅ 116
Length mm 615 790
Weight kg 30 23
Stroke mm 200 200
Ram area mm² 4 926 4 710
Maximum pressure bar 467 488
Maximum force kN 230 230
Presence of seating ram ? No Yes
The drawing on Page 28 indicates the clearances to be introduced around the anchorages at the ends of the
post-tensioned structures in order to facilitate installation.
4.1.2 HYDRAULIC PUMPS
The VSL pumps comprise the assembly of hydraulic components including: pumps, distributors, nozzles and
safety valves. The pumps are typically driven by electric motors.
The stations themselves have been dimensioned for normal stressing speeds and contain safety measurement
devices that depend on the specific application.
4.1.3 INSTRUMENTS AND MEASURING SYSTEMS
STRESSING
The VSL force and elongation measurement instruments or systems serve to control with precision the stressing
operation and display the results obtained.

Annex 2 of the European Technical Approval No ETA-06/0006 19
4.2 PROCESSES OF STRESSING AND CONTROL PROCEDURE
Before proceeding with cable stressing, a certain number of preconditions must be met, in particular:
- all pertinent safety rules and recommendations must be fully known;
- the force targets along with the corresponding values of elongation; moreover, tolerances must be known by
the PT Supervisor, who will have applied any eventual necessary adjustments to these values in order to
account for parameters specific to the equipment;
- the order in which the prestressing cables are to be stressed must be specified, and the order in which the
strands in the cables are to be stressed with S 6-4 anchorages must be known;
- the stressing equipment (including measurement instruments) must comply with guidelines furnished in the
present ETA;
- the required strength of the concrete of both the structure and anchorage zone undergoing stressing must be
verified;
- the loading and support states of the structure associated with the stressing phase must also be verified;
- the over lengths of the strands to be stressed must remain perfectly clean.
It should nonetheless be recalled that during the stressing process, it is strictly forbidden to be positioned behind
the jack or within its immediate vicinity. The same precautions must be taken for the area in the back of the
accessible dead-end anchorages.
Even though the VSL system does not require any locking accessory device, with some jacks, the wedges may
be set in order to reduce the setting of anchorage wedges and its influence on the force (abscissa function) in
the strands.
4.2.1 FORCE MEASUREMENTS
The measurement of force in the cable, as transformed into pressure measurement in the jack, is generally the
assigned objective herein.
The pressure existing in the jack chamber is indicated by the manometer installed on the pump, with eventual
control of the jack. The manometers used (Accuracy 1%), regularly recalibrated using a scale, feature a
guaranteed precision of 1% of their maximum pressure, which tends to lie at 490 bars; these instruments
thereby provide a precision of 5 bars over the entire manometer scale.
In order to obtain the effective force on the structure, the force resulting from the manometer reading is to be
corrected for losses inside the jack as well as for losses due to friction of the strands in the anchorage.
Losses inside the jacks are identified from intrinsic hardware data. Although they contain an independent
pressure term and another closely-proportional term, submitted to the maximum pressure reached upon
completion of the stressing operation, the losses inside jacks are solely expressed in proportional terms and
exhibit the following values:
- DKP 6 jack: 3.5%
- ZPE 23 FJ jack: 1.5%
The losses in active anchorages, named ka, are due to friction of the strands deviated on the component parts
and, depending on the specific anchorage, exhibit the following values:
- S 6-1 anchorage: 0% to 1%
- S 6-4 anchorage: 0% to 1% for the two central strands, 2% for the two outside strands.
4.2.2 ELONGATION MEASUREMENTS
The measurement of cable elongation is generally a control measurement that provides information on cable
behavior during stressing.
As for elongation measurements, an index is installed on the strands. During the stressing operation,
elongations are then deduced from measurements of the displacement of this index. Since the onset of
displacements combines the seating of tendons in their ducts with their actual elongation, the elongation during
initial displacements is obtained by means of extrapolating the pure elongations occurring subsequently.
The various pressure-elongation relations noted during cable stressing are recorded in the stressing data
sheets, which are to remain available.
Section 2.7.2 provides a recap of the elongation evaluation basis used during the stressing operation.

Annex 2 of the European Technical Approval No ETA-06/0006 20
5.1.1 UNBONDED SYSTEM
CHAPTER 5
5.
5.1 INJECTION
The monostrand (individually greased and sheathed), protected from the factory by grease, obviously does not
necessitate any special additional protection.
The S 6-1 and S 6-4 anchorage units, after stressing and cut-off of the strands, are filled with grease (identical
or compatible with that of the monostrand in compliance with the ETAG 013) by means of injection using a
pump. Following filling, a cap serves to enclose the strand ends and the wedge housings.
5.1.2 BONDED SYSTEM
INJECTION AND SEALING
- General information:
The nature and composition of injection products for the permanent protection of tendons and anchorages and
for their bonding to the structure are not inherent to the prestressing process; instead, they depend on the
project and the structure's assigned purpose.
The products involved must not be a threat to the hygiene, health and the environment.
In addition to the specific clauses relating to dangerous substances contained in this European Technical
Approval, there may be other requirements applicable to the products falling within its scope (e.g. transposed
European legislation and national laws, regulations and administrative provisions) In order to meet the
provisions of the EU Construction Products Directive, these requirements need also to be complied with, when
and where they apply.
The products used for the permanent protection of post-tensioning tendons and anchorages implemented by
means of injection may be categorized as follows:
Hydraulic cement-based injection grouts are the most commonly employed. These products may pertain
to common grouts defined in the standard EN 447 or special grouts that make use of performance-enhancing
admixtures. In some regions of the EU, unfavorable climatic conditions impose the application of special grouts
according to ETAG 013.
Those injection products that have already received a European Technical Approval may also be used in
respect of the prescribed set of uses.
Completion of the tendon envelope in the anchorage zone is provided during the time of injection by means of
either temporary waterproof caps or definitively by permanent caps.
- Injection equipment:
The set of injection equipment has been adapted to the specific products to be injected.
For the cement-based grout, the VSL injection equipment is composed for the most part of mixers and pumps
integrated into a single device that enables preparing the grout and performing the injection. This equipment
makes it possible to allocate with precision the grout components and to obtain a perfectly-homogeneous mix.
The pump with which the equipment is fitted has been designed for continuous injection at an adapted grout
progression speed.
- Injection procedures:
Before proceeding with the injection of a permanent cable protection, a certain number of conditions must be
fulfilled and in particular:
- The injection product must comply with the terms of the present ETA and the ETAG 013;
- The injection equipment must comply with indications laid out in the present ETA,

Annex 2 of the European Technical Approval No ETA-06/0006 21
- The waterproof sealing of the tendon and anchorage envelopes (ducts, fittings, pipes and caps) must be
verified,
- The climatic conditions and temperature of the structure must satisfy the use conditions of the injection
product.
The primary controls conducted during injection consist of verifying the adequate filling of the duct by means of
inlets, bleed vents and outlets laid out all along the cable path and verifying that the product discharged by the
vents or outlets displays the required properties.
Grouting procedures and grouting surveillance shall be carried out according to EN 446.
As an initial approach, the injection product quantities per unit cable length will be derived from:
[(internal duct section area - tendon section area) × (unit length)] × (1 + ξ), where ξ is such that: 0.05 ≤ ξ ≤ 0.10
in order to incorporate worksite losses, the shape of the duct and eventual corrugations.
The various phases and parameters associated with cable injection are to be recorded on the injection data
sheets, which are to remain available.
5.2 SEALING
The continuity of protection against all types of aggressions must be ensured all along the cable up to and
including the anchorages.
The protection measures introduced for this unique zone, which is located at the end of the slab and frequently
protected from external aggressions is most often limited in this case to the filling of the block-out with mortar or
concrete. In the case of end zones exposed to aggressive environment additional protection measures may be
necessary (permanent cap or waterproof lining).

Annex 2 of the European Technical Approval No ETA-06/0006 22
CHAPTER 6
SCHEMATIC DRAWINGS
(dimensions expressed in mm)
Title Page
STANDARD ANCHORAGE ELEMENTS
Wedges see Annex 1
ANCHORAGES
Type S 6-1 anchorages
Principles of both the "unbonded" and "bonded" systems 23
Sizes 24
Type S 6-4 anchorages
Principles of both the "unbonded" and "bonded" systems 25
Sizes 26
Type H 6- (1 through 4) anchorages see Annex 1
REINFORCEMENT OF ANCHORAGE ZONES 27
CLEARANCE REQUIREMENTS 28
DUCTING 28