Response of perforated pipes buried in sand under lateral soil–pipe movements

The use of perforated pipes is increasing in many applications to facilitate drainage/infiltration of liquid through opening channels in the pipe wall. However, the design of perforated pipes lacks consideration for lateral soil–pipe interaction induced by differential ground movement, which can generate large pipe stresses and strains. In this study, in-air three-point bending tests were conducted on perforated pipes, which were subsequently evaluated through lateral dragging tests. The mechanical responses of perforated pipes with different hole diameters, spacings between holes, and layer number of opening holes were interpreted. It was found that the load–displacement curves for all tests generally did not show significant differences. The pipe wall thickness had a significant impact on midspan deflection, reflecting by the smallest midspan deflection due to a higher flexural rigidity. All the tested perforated pipes were safe, since the maximum pipe strains were well below the linear elastic limit of 3% for polyvinyl chloride material. The efficacy of two prediction methods from the literature was also assessed: one was found to provide relatively close estimations, while the other solution was found to be suitable for use at relatively small pipe end displacements before the mobilization of peak soil resistance.