Page 178 - Trenchless Technology Piping Installation and Inspection

144 Cha pte r F o u r

The pipe sections are cast vertically with an inner and outer form
and are vibrated for compaction. After the forms are removed, the
section is heated in a kiln to finish curing the resin. These pipes can
typically be used to carry highly aggressive wastes, for pipe jacking
as they have very high compressive strengths (up to 17,000 psi), or for
microtunneling. They can also be used for gravity flow or pressure
applications. Some manufacturers are also making polymer pipes
in sizes appropriate for use as manholes. Also, semielliptical and
circular liner pipes have been developed for sliplining sewers. There
are several ASTM standards for the product.
Polymer concrete pipes have several benefits including high
strength, corrosion resistance (they can be used in environments with
pH ranges of 1 to 13), low wall roughness, and high abrasion resistance.
The use of polymer concrete pipes is becoming more common in the
following areas: direct bury, sliplining, jacking and microtunneling, tun-
neling, and above-the-ground applications. One of the main disadvan-
tages in the past was the high cost associated with importing the pipe;
its high cost relative to alternative materials limited its use to only niche
markets where its superior qualities were needed. Another characteris-
tic to be accounted for especially in the larger diameters is that, since it
is nonreinforced, PCP can only exhibit a brittle failure mode if the exter-
nal load-bearing capacity is exceeded. However, since 2002, polymer
concrete pipe has been manufactured in the United States under the
brand name of Meyer pipe. This is now enabling competition with
products such as glass-reinforced pipe (GRP) for jacking installations.
Fiberglass sleeve joints are made separately, with elastomer seal-
ing and spacing rings laminated into the sleeve. Factory fitting of the
couplings to the end of the pipe is performed and pressure testing is
done up to 35 psi. As an alternative to the couplings, stainless steel
collars are also available.

Applicable Standards Table 4.5 lists reinforced concrete pipe stan-
dards that are widely used in trenchless installations. Typical avail-
able diameter ranges are also given.
Joint Types The concrete pipe industry has developed several different
types of joints for the various types of pipes. Selection of the appropriate
joint is based on the stringency of the application for water tightness.

Pressure Standards Nonpressure Standards Available Diameters (in.)
ASTM C361 — 12–108
AWWA C300 — 30–144
AWWA C302 — 12–144
— ASTM C14, C76, C655 12–144

TABLE 4.5 Concrete Pipe Standards