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

Technology/Method Fold -and - Form/Thermoformed
Design Life Range 100 year claimed [4],[5], but not field-demonstrated; long-term material data
testing and creep strain analysis offered as evidence of claim.
Installation Standards ASTM F1867
ASTM F1947
Installation The Ultraliner PVC Alloy pipeliner is pulled into the cleaned host pipe, usually
Methodology through a manhole. Access is required at both ends. Once in place, the ends are
plugged and the pipeliner expanded with steam and air pressure (thermoformed)
to reset the PVC Alloy’s “memory” to the new size and shape. Installation and
processing of the liner takes 4 to 5 hours, excluding the time to reinstate laterals
and some street operations set-up and tear down time.
QA/QC Design material properties are quality assured at the manufacturing facility per
ASTM product standards (F1871 or F1504) using industry standard QA/QC
protocols common to the manufacture of all PVC pipes. Specification
compliance is confirmed prior to installation. Standard industry post-construction
QA/QC tests are available for further verification.
IV. Operation and Maintenance Requirements
O&M Needs No special maintenance training is required. Any cleaning or de-rooting
procedure routinely practiced by maintenance personnel within PVC pipes is safe
for use within PVC Alloy pipeliners. The host pipe can easily be removed
(hammer a rigid host pipe to shatter it) without damaging the pipeliner, if new
connections or repairs need to be made in the future. Standard fittings, couplings,
and saddles are readily adaptable for use with PVC Alloy Pipeliners.
Repair Requirements PVC Alloy pipeliners are capable of structurally lining and conforming to
for Rehabilitated crushed sections of pipe and severe off-sets. Repair decisions are therefore
Sections generally driven by system performance and long-term O&M requirements rather
than constructability limitations.
V. Costs
Key Cost Factors PVC Alloy Pipeliners have relatively low set-up, mobilization, and shipping &
handling costs. Materials are shelf-stable (do not have to be temperature
controlled) and can be affordably shipped one reel at a time or in bulk
(thereby enabling payment for stored materials where appropriate).
• Extensive cleaning of the host pipe, above and beyond what is considered a
routine pipe maintenance cleaning project, is required for all tight-fitting
liners.
• On gravity pipes, no excavation is required, providing significant savings.
Access can be achieved through a manhole ring on one end and at least a
clean-out on the other end. Laterals are robotically reinstated internally.
• Pressure pipes frequently require excavation at the ends (and in the middle
where maximum lengths have been exceeded), at valves and hydrants, and at
connections. This can significantly impact cost-competitiveness against
alternative technologies that can avoid excavation.
• De-watering is not required for quality assurance, as water exposure cannot
alter design property compliance of a solid wall PVC Alloy Pipeliner, but it
may be utilized for risk control, as appropriate, since excessive groundwater
can narrow the window of installability.
• The material cost is all inclusive (and includes manufacturing QA/QC) with
no additional on-site mixing of chemicals, nor “finishing” labor
requirements prior to installation.
• End seals, when specified, are routinely included in the unit price for the
pipeliner.
• Lateral reinstatements are generally a separate cost because the numbers of
connections vary.
• PVC Alloy pipeliners tend to be more competitive on small scale (short
lengths, small diameter) projects given low mobilization and set up costs
compared to other trenchless rehab methodologies.
Case Study Costs GDOT- seven deteriorated culverts, ranging in diameter from 15 inches to 30
inches and 40 to 80 feet in length were lined for a total cost of $43,288. This was
34% less than the bid price of $65,674 to dig-and-replace. Generally speaking,
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