本研究以典型埋地PE管道-基土为原型，通过自主设计的管道试验系统，开展了堆载作用下埋地PE管道力学响应过程的模型试验。结果表明：堆积荷载对管道的力学性能有显著影响，管周应变峰值出现在堆载下方并向管道两端递减。管道横截面在竖向应力作用下呈对称应变发展。管道应变为非线性增长，经历缓慢和快速增长两个阶段，增长幅度分别为40%和76.3%。管道与土壤的相互作用导致管道同一轴向呈现不同的受力状态，但大体表现出轴向拉伸。同时，管-土相互作用下管道的弹性恢复被抑制，管道呈现梁式弯曲，出现类挠曲线形态。此外，管道两端受约束及土抗力作用产生小幅度的反方向位移。上覆土层随着管道变形出现陷落或隆起，附加堆积荷载逐渐向深层扩散并消散。

In this study, a typical buried PE pipe model test under the action of stacking load was carried out by means of an independently designed pipeline test system. The results show that the accumulation load has a significant effect on the mechanical properties of the pipeline. The peak of the strain around the pipe appears below the load and decreases towards both ends of the pipe. The strains on the cross section of the pipeline develops symmetrically under vertical stress. The strain of the pipeline is non-linear, and it goes through two stages of slow and fast growth, with the increase rates of 40% and 76.3%, respectively. The interaction between the pipeline and soils results in different stress states in the same axial direction while the pipeline generally shows axial stretching. Simultaneously, the elastic recovery of the pipeline is inhibited under the pipe-soil interaction, and the pipeline presents a beam-type bending and a flex-like shape. Additionally, both ends of the pipeline are constrained and the soil resistance produces a small degree of reverse displacement. The overlying soil sinks or rises with the deformation of the pipeline, and the additional accumulation load gradually diffuses to the deep layer and dissipates.

四川省自然科学(2022NSFSC0429)；中国博士后科学基金(2021M692697)；四川省科技计划项目(2024NSFSC2007)