What determines the load that a pipe must support after backfilling?

• A. Trench width and depth
• B. Pipe material composition
• C. Ambient temperature
• D. Pipe diameter

Answer: (A)

The load that a pipe must support after backfilling is primarily determined by the trench width and depth. When a trench is excavated to install a pipe, the dimensions of that trench can influence how much soil and other loads are placed on the pipe once it is covered. A wider or deeper trench may require a pipe to support different soil loads and stress conditions than a narrower or shallower trench.

The width of the trench affects the amount of lateral earth pressure exerted on the pipe, while the depth of the trench relates to the vertical load of the overlying soil. As the depth increases, the weight of the soil above increases, which can lead to greater pressure being applied to the pipe. Therefore, trench dimensions are crucial in determining the structural integrity and the load-bearing capacity required from the installed pipe, ensuring that it can handle the pressure without failing.

Other factors such as the pipe's material composition, ambient temperature, and diameter certainly have roles in a pipe's overall performance and longevity but do not primarily dictate the loads resulting from backfilling.