A computational framework to predict the water‐leakage pressure of segmental joints in underwater shield tunnels using an advanced finite element method

Abstract

Summary The construction of shield tunnels under riverbeds and seabeds has considerably increased over the past decades. Due to the ultra‐high water head, water leakage through tunnel joints is a major concern during a tunnel's service life. One practical solution to prevent groundwater penetration is to implement ethylene‐propylene‐diene‐monomer gaskets at the segmental joints. However, numerical simulation of fluid pressure penetration into rubber materials remains a challenging problem in computational mechanics. Severe mesh distortions can occur due to large deformation. Consequently, a convergent solution is difficult to achieve. This paper presents an Abaqus‐based numerical framework to solve the previously mentioned problem using the implicit finite element solver. The key aspects of this framework are twofold: (1) a remesh and re‐map algorithm to overcome the excessive mesh distortion, and (2) simulation of fluid penetration into the contact interface of the gaskets to reproduce the water‐leakage process at the tunnel joints. The proposed framework is first tested to simulate the gasket‐in‐groove mechanical behavior and is then validated using experimental data and the solution produced by an explicit finite element solver. The developed framework is then adopted to predict the water‐leakage pressure at gasketed tunnel joints to illustrate the practical applications. Finally, the numerical results are compared with experimental data to demonstrate the accuracy and robustness of the proposed method and confirm its superiority and effectiveness over existing methods. This novel method can be used by tunnel designers to analyze and estimate the waterproof behavior of gasketed joints in shield tunnels without performing extensive experimental testing works.

Characteristic parameters’ optimization based on contact pressure of sealing gasket for segmental joints

“…The form of the open holes is similar to the ''straight wall top arch section'' in tunnel engineering. From the statistical literature, 2,4,6,10,12,15,17,18,20 the form is almost unchanged. However, there are many forms of the closed holes, as shown in Figure 1(b).…”

“…As for the influence of the gasket holes opening rate on the sealing gasket waterproofing, based on the previous research conclusions, 4,5,6,8,10,12,14,21,22 the gasket model in this section will adopt the ''Sheffield'' section with double-row circular staggered holes. The influence of the area change of closed holes portion (orange), open holes circular portion (blue), and open holes trapeziform portion (green) on the waterproof performance of the sealing gasket was studied with the opening rate as the control variable.…”

“…W Ding et al 12 studied the waterproofing design of shield tunnel sealing gasket on Weisan Road in Nanjing. C Gong and Ding 4 obtained a calculation formula for contact pressure and water pressure of sealing gaskets by combining test and numerical analyses data. The influence of geometric sizes change caused by production technology on waterproofing was analyzed by ZY Lei and Liu 17 Based on the specific project, K Xiang and Shi 18 adopted ANSYS numerical simulation method to optimize the design of sealing gasket section.…”

“…Water leakage is all along one of the potential problems of underground structures. [3][4][5][6] It has become a topical issue for segmental joints of shield tunnels during the construction and the operation stages. However, characteristic parameters of sealing gasket in shield tunnels have been seldom obtained.…”

“…[7][8][9][10] A series of research works on the waterproofing design of sealing gasket segment joints have been carried out. 4,[11][12][13] For instance, Tuo et al 14 studied the design of ultra-high water pressure shield tunnel sealing gasket by physical test, and analyzed the waterproofing performance of several section forms. Z Ming et al 15 conducted compression test and waterproofing test to study the sealing gasket form of high water pressure tunnels in Shanghai.…”