Minimum Trench Width Calculation in the US for Various Pipe Materials
How to Calculate the Minimum Trench Width for Centrifugally Cast Fiberglass-Reinforced Polymer Mortar Pipes?
The table below presents the minimum trench width as a function of pipe outside diameter for centrifugally cast glass-fiber reinforced polymer mortar (CCFRPM) pipe installation using the open cut method.
Table:
Minimum trench width for centrifugally cast, glass-fiber-reinforced, polymer mortar (CCFRPM) pipe as per [HOBAS CCFRPM Guide]
Minimum Trench Width Calculation Formula Based on Pipe Outside Diameter (OD) | ||
Pipe OD (in) | Minimum Distance on Each Side of the Pipe (in) | |
SPT* ≤ 8 | SPT* ≥ 8 | |
18 to 20 | 6 | 4 |
24 to 33 | 9 | 6 |
36 to 48 | 12 | 8 |
51 to 72 | 18 | 12 |
78 to 126 | 24 | 16 |
*SPT = Standard penetration test blows/ft. as per [ASTM D1586]