Multiscale Analytical Method and Its Parametric Study for Lining Joint Leakage of Shield Tunnel

Featured Application This study could provide a shield lining joint leakage calculation and analysis model. Understanding the underlying processes of lining joint leakage is essential for predicting its waterproofing performance, improving the design, and assessing its operational health in shield tunnels. There is little literature reported on a leakage model that can reflect various influencing factors. This article introduced an analytical method for predicting joint leakage based on recently developed multi-scale contact mechanics: the Persson model. In addition, the critical leakage state and the self-sealing effect were defined, and an approach to calculate the critical leakage pressure, as well as self-sealing stress, were deduced. Then, taking the second Dapu Road Tunnel in Shanghai as a case study, the influence of various factors, including the gap and offset of joints, the roughness of sealing materials, the service time, and groundwater pressure on the lining joint leakage, was calculated. The applicability of the model was verified by comparing the calculated results with the experimental data and monitoring data in the literature. This research could contribute to understanding the development process of seepage in sealing engineering and provide a reference for waterproof design and the performance assessment of shield tunnels' lining joints.