Installation Manual - Future Pipe Industries

9.3.1. Other methods of back filling
Use of the saturation method does not give any better results than the method already described. If the saturation
method is used the compaction may be disturbed. Ensure the pipe does not float and the sides are not eroded during
water injection. Do not backfill if the ground is already saturated. This method may only be used for free draining soils
or when the drainage pumps are kept running and the pipe system is completely filled with water.
9.3.2. Pipe systems to be cast in concrete
Do not pour concrete directly onto the pipe. Compacting in the surronding area of Wavistrong pipes is not allowed.
The vibrating needle must be kept at least 30 cm from the pipe.Prior to casting, the pipe system must be pressure
tested (see chapter 11). In order to prevent the pipe from floating concrete cradles provided with steel clamps and rubber
lining can be used (see fig. 9.3.b.). Support distance has to be calculated. Consult Future Pipe Industries. Buckling of
the pipe during casting can be prevented by pressurizing the system. This also reduces the bending caused by the boyancy
of the pipe. Please note that as the concrete sets there will be shrinkage and this will increase the pressure in the
system. Ensure the permitted pressure is not exceeded by the use of pressure relief valves.
Fig. 9.3.b.
Wavistrong Installation Manual
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