Mechanical Properties and Structural Optimization Analysis of PVC Axial Hollow-wall Pipe for Drainage

Axial hollow-wall pipe has many advantages, such as material saving, lightweight and easy construction, and low cost. Innovating its structure enhances these advantages. Based on external pressure, internal pressure, impact resistance, and buried ground model test and simulation analysis, the basic mechanical properties of arch-hole axial hollow-wall PVC pipe are analyzed. Then, through finite element analysis, a comparative study is conducted on structural wall pipes with different hole shapes and solid-wall pipes, and the influence mechanism of structural wall hole shapes is examined. Finally, the influence of pipe wall layout on pipeline stiffness and strength performance is assessed. The results show that with increasing deformation, the ratio of the external pressure-bearing capacity of solid-wall pipe to structural wall pipe increases gradually, indicating that the stiffness of the structural wall pipe deteriorates rapidly. The mechanical properties under external pressure, internal pressure, impact resistance, and buried ground conditions all demonstrate that the hole shape effect follows the order: circular hole > arch hole > rectangular hole. The cross-sectional moment of inertia of the hollow-wall pipe with circular holes is relatively large, and its deformation resistance is the highest among hollow-wall pipes. The deviation of the hole center toward the inner wall improves the ring stiffness. Due to the specific stress form of axial hollow-wall pipes, the arc length of the hole angle in the circular hole hollow-wall pipe increases the effective wall thickness and reduces stress concentration, resulting in relatively lower stress under load. The circular hole structure should be preferred for axial hollow-wall structures, and selecting the number of holes and eccentricity of hole centers based on different dominant working conditions can further enhance structural performance. This study provides technical support for the structural design of hollow structural wall pipes, uses the advantages of structural wall pipes, and expands the variety of drainage pipes.