It is crucial to ensure the safety and stability of pipelines buried in slopes during installation and operation. In this paper, the interaction between a pipe and soil was investigated via laboratory model tests. The effects of the slope angle and pipe position on the slope horizontal deformation and pipe mechanical properties were investigated. Furthermore, the restraint effect of tire strip reinforcement (TSR) on slope deformation and its impact on pipe stress and strain were analyzed. The results revealed that the potential sliding surface is located at the middle of the slope. The pipe location has a significant effect on the horizontal surface deformation of the slope, whereas the slope angle has a small effect on the stress and strain of the pipe. In addition, the use of the TSR not only reduces the horizontal surface deformation of the slope but also partially alleviates the vertical stress on the crown of the pipe. As the pipe moves away from the loading plate, the circumferential stress distribution changes from a symmetric state to an asymmetric state, with the most critical location moving from the spring line to the top. The test results provide reliable experimental data to support the design of pipes buried within a slope.

Precisely evaluating the soil pressure above parallel tunnels is of paramount importance. In this study, the deformation characteristics of soil above dual trapdoors were analyzed firstly. A novel multi-arch model for calculating the distribution of the vertical earth pressure on deep-buried parallel tunnel was then proposed based on the limit equilibrium method. The height of the dual arch zone caused by the displacement of the dual trapdoors was calculated with consideration of internal friction angle of the soil, width of the trapdoors, spacing between the dual trapdoors, and elastic modulus of the soil. By comparing with numerical simulation results and existing theoretical calculation models that do not account for the interaction of soil arching effect, it is evident that the proposed model in this study adeptly predicts the vertical stress above the trapdoor. Additionally, it captures the characteristic of upwardly convex stress distribution above the trapdoor. The analysis of parameters conducted on the theoretical calculation model showed that the depth of the trapdoor and the internal friction angle of the soil have a substantial impact, whereas the expansion coefficient exerts a negligible effect on the soil arching ratio above the trapdoor.