Research on the Jacking Force of PVC Pipes Utilized in Microtunneling

Abstract

The lower stiffness of PVC pipes results in more complex pipe–soil interactions, making it difficult to accurately assess jacking force using existing specifications. A soil pressure calculation model of PVC pipes that considers pipe deformation was proposed. The corresponding model can be used for the jacking force estimation of PVC pipe jacking. Furthermore, the factors that influence the jacking force of PVC pipes are analyzed through finite-element numerical simulation. The results indicate that the circumferential pressure of PVC pipes will change due to pipe deformation. The predicted upper limit is approximately 1.42 times the measured maximum value, and the maximum error between the predicted lower limit and the measured value does not exceed 15%. The jacking force predicted by finite-element simulation is close to the measured value. The parametric analysis indicates that the jacking force decreases with the internal friction angler of the soil and the amount of overcut and as the diameter of the pipe increases.