Trench width should be measured “dirt to dirt” at the top of the pipe barrel (not stopping at the trench box). The trench width should not exceed the design specification.

The foundation is the basis on which the entire pipeline is built.  A firm and unyielding foundation will ease installation and eliminate problems associated with movement during later phases of construction.

Project specifications designate a minimum bedding class requirement to achieve the appropriate factor of safety.  Adherence to the minimum bedding class specified is critical to ensure the installation will support the backfill load.

Bell holes are critical for ensuring that the load is supported by the pipe barrel and for preventing a point load on the bell.

Haunching ensures uniform support of the pipe and must be performed before the bedding material is no higher than the quarter point of the pipe barrel.

Walk-behind and hand-held, light compaction equipment can be used in the trench and at cover depths of less than 5 ft.

All of our workshops and handbooks are offered at no charge to help ensure successful installations.

Contact us at info@ncpi.org or 262-742-2904.