State of Technology Report for Force Main Rehabilitation, Final ...

Dimensional checks on the pipe diameter and wall thickness are also included. The pipe flattening and
impact requirements are designed to primarily ensure that the pipe can be folded and reformed during the
installation without damage, while the stiffness and flexural properties relate to the design. There are no
QC requirements on measuring tensile strength, while the Type A material is to be made from virgin PVC
with a minimum tensile strength of 3,600 psi (248 bar).
Neither of the ASTM standard practices for the installation of folded PVC pipes (F1867 and F1947) is for
pressure applications. Consequently, the only field QC requirements pertain to gravity service. A low
pressure leakage test with a limiting exfiltration level of 50 US gallon/inch diameter/mile/day is
recommended. Samples of the rounded pipe are also retrieved at the insertion point, with diameter,
thickness and flexural properties measured. For the Type A material, ASTM F1867 also includes testing
for tensile properties (3,600 psi [248 bar] minimum).
5.6.1.2 PE Short-Term QA/QC Requirements. In pressure applications, the majority of the
rehabilitation that has been undertaken with PE pipe has been either with pipe bursting or sliplining.
Pipes used in these applications normally meet either AWWA C901 or C906, or the ASTM specification
for OD controlled pipe, ASTM D3035. Typical factory QC requirements in each case include visual
inspections for workmanship (no cracks, holes, foreign inclusions, etc.), diameter and wall thickness
checks, density measurements (per ASTM D1248), sustained pressure tests (subject the wall to a hoop
stress equal to the hydrostatic design stress), burst pressure tests (1.6 times the HDS for PE 3408),
environmental stress cracking tests, elevated temperature sustained pressure tests, and apparent ring
tensile strength tests.
In the case of sliplining, the original pipeline is visually inspected in the field by CCTV to locate problem
areas, including offset joints, crushed walls, obstructions and the location of service connections. The
only ASTM standard practice for the insertion of PE pipe, F585, is for gravity applications and includes
only a low pressure exfiltration test for acceptance, which is not particularly useful in a force main
application. The AWWA M45 PE Pipe – Design and Installation manual provides some guidelines on
the use of PE pipe for pipe bursting and sliplining, but does not contain any specific field QC test
requirements except recommending a hydrostatic pressure test for acceptance.
Deformed PE
In the factory, deformed PE liners are dimensionally checked, plus evaluated for ESCR, tensile strength,
tensile elongation, and flexural modulus. These tests are part of the normal qualification and QC
requirements. The PE liner is required to have a minimum HDB, which would previously have been
demonstrated through type testing. The HDB rating of the resin is used for pressure design. The only
ASTM standard practice for the insertion of a deformed PE liner in a sewer, ASTM F1606, is for gravity
applications. QC requirements include a CCTV inspection of the liner after insertion and reversion, an
exfiltration or low pressure air test for leakage, and taking samples at the insertion or termination point for
further analysis. This would include diameter and wall thickness checks, plus measurement of flexural
modulus and tensile strength.
5.6.1.3 CIPP Short-Term QA/QC Requirements. As such, there are no ASTM CIPP product
specifications covering pressure applications, but ASTM D5813 Standard Specification for Cured-in-
Place Thermosetting Resin Sewer Pipe does require the fabric tube to have a minimum tensile strength of
750 psi (52 bar). This pertains more to handling and insertion needs than actual in situ performance.
Once the CIPP liner is installed, the recommended QC practice in all of the ASTM standards is for
samples to be cut from a representative section of the cured CIPP liner and then tested for short-term
flexural strength and modulus and short-term tensile strength. Two methods (ASTM D3039 and ASTM
68