为探究可控低强度材料（controlled low-strength materials, CLSM）回填下的埋地管道力学特性，利用土箱试验，分别以普通砂和CLSM作为回填料回填埋地硬聚氯乙烯（unplasticized polyvinyl chloride, UPVC）管，通过对比分析静载作用下普通砂回填和CLSM回填后柔性管道的变形、应变以及管周土压力变化情况，进一步明确CLSM回填埋地柔性管道的作用规律。结果表明：相较于砂土回填，采用CLSM回填可以在一定程度上减小柔性管道的径向变形，尤其是竖向变形；CLSM包裹管道后，竖向传递的荷载主要是由管侧而非管顶的CLSM来承担，能够减小管顶的竖向压力；CLSM回填会减弱柔性管道上方区域的土拱效应；CLSM回填改善了管道的整体受力，从而显著降低了管道的应变，能对管道进行很好的保护。该研究结论可为CLSM在埋地柔性管道回填中的实际应用提供理论指导。

In order to explore the mechanical characteristics of buried pipe under CLSM(controlled low strength materials) backfill, the soil-bin test was used to backfill the buried UPVC (unplasticized polyvinyl chloride) pipe with ordinary sand and CLSM respectively. By comparing and analyzing the deformation, strain and earth pressure variation around the pipe after traditional sand backfill and CLSM backfill under static load, the action law of the flexible pipe in the CLSM backfill was further clarified. The test results show as follows. Compared with sand backfill, CLSM backfill can reduce the radial deformation of the flexible pipe to a certain extent, especially the vertical deformation. After the CLSM wraps the pipe, the vertical load is mainly borne by the CLSM on the side of the pipe instead of the top, thus reducing the vertical pressure on the top of the pipe. CLSM backfill will weaken the "soil arch effect" in the area above the pipe. CLSM backfill improves the overall force of the pipe, thus significantly reducing the strain of the pipe and protecting the pipe well. These conclusion of this paper can provide theoretical guidance for the practical application of CLSM in the backfilling of buried flexible pipes.