Mechanical response of buried HDPE double-wall corrugated pipe under traffic-sewage coupling load

A high-density polyethylene (HDPE) double-wall corrugated pipe is a flexible plastic drainage pipe. The backfill compaction, the external load, the sewage in the pipe, and the strength of a pipe determine its strain distribution. In this paper, a real three-dimensional model of a high-density polyethylene double-wall corrugated pipe is established by using ABAQUS and ANSYS, and the coupling simulation of pipe-soil-fluid under real conditions is realized. A full-scale prototype verifies the feasibility of the model. According to the strain distribution of the pipe obtained by numerical simulation and the constitutive structure of the high-density polyethylene material, the local bending and creep development of the pipe are predicted. The results reveal that the deformation of the pipe is dependent on the three factors (backfill compaction, sewage volume, and flow speed) and independent of the sand in the sewage. The backfill compaction determines the approximate distribution of pipe strain, while sewage reduces the strain on the interior wall. The sewage causes the tensile strain of the interior wall near the invert, increasing the possibility of local bending. Over time, the strain of the pipe increases due to creep, and local bending develops rapidly.