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

pipe’s design life. Once again, it would be reasonable to expect that any renewal liner using PVC
material would be affected similarly by cyclic loading and should be designed accordingly.
5.2.4 Other Considerations. Force mains do not have frequent service connections as in a water
main, but nonetheless there are usually pressurized connections to other incoming or outgoing mains, air
release valves at high points, and other inline fittings (valves, elbows, etc.). The protocol with practically
all force main rehabilitation systems, except independent slipliners, is to terminate the liner with a special
mechanical fitting that seals the end of the liner with the existing host pipe, and then incorporate a ductile
or CI fitting for the connection to the fitting or valve. Slipliners, such as full thickness PE and PVC pipes,
can be re-connected in the same manner as ordinary pipe made of these same materials. Electrofused
fittings for PE and DI fittings for PVC are common.
Another important design consideration in a renewal project is the intended design life of the rehabilitated
system. The renewal can be a fully structural replacement for the existing pipe, in which case a design
life of 50 years is desired. Or, the renewal may only be a corrosion barrier (Class I) or a close-fit semistructural
liner (Class II or III) with a design life dependent on the continued structural performance of the
existing pipe. If the existing pipe is incapable of handling the internal pressure due to external corrosion,
then the design life of the renewal liner is going to be limited to that of the existing pipe. As reported in a
recent report (WERF, 2009), the majority of sewer force mains are under 25 years of age with few over
50 years, which is quite different from the age distribution of the nation’s water distribution system.
Consequently, it is reasonable to expect that any renewal liner should be able to extend the design life of a
sewer force main for at least another 25 years.
5.3 Product/Material Standards
The two main national organizations within the US that undertake development of consensus standards
covering materials, products, testing methods and installation methodologies are ASTM and the AWWA.
These bodies provide a forum for producers, users, and those having a general interest (e.g., government,
academia) to write standards that best meet their needs. Representatives from each interested field are
involved in the standards process, but the producer community normally takes a leading role. AWWA
standards are solely dedicated to the water industry. Some products or linings that are used in the water
industry may also have a place on the wastewater side. Epoxy linings are a good example of dual
potential use. The National Association of Sewer Service Companies (NASSCO) has also developed
some excellent guideline specifications and manuals of practice. Producer companies are solely involved
in the NASSCO specifications so the user community’s interests may not be fully appreciated.
The body of standards can be broken down into four areas – product/material standards, design standards,
and installation standards, and manual of practices. Some of the standards serve more than one purpose.
The purpose of this report is not to provide a detailed review of each pertinent standard, but rather to
highlight some of the more important standards and especially those that are relatively new within the
past 5 years and may have a use for sewer force main renewal.
ASTM Product/Material Standards
This section summarizes product/material standards by pipe type including those defined for PVC, PE,
CIPP, and FRP/GRP materials.
PVC Materials
The following ASTM standards in Table 5-1 cover PVC materials used for renewal.
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