Abstract To address the problem of long-term operational safety degradation caused by water leakage in the joints of shield tunnels, this paper develops a numerical calculation model for joint leakage and analyzes the mechanical response of the segment structure with water leakage in the joints. The results show that water leakage in the joints could lead to a significant reduction in the external water pressure borne by the segments in the vicinity of the joints, and the reduction increases with the increase in the amount of leakage; the variation of internal force of the segment structure would experience three stages of rapid increase, slow increase and stabilization along with continuous leakage; a positive correlation exists between the magnitude of structural bending moments and axial forces and the amount of joint leakage; when the total leakage volume in the joints is the same, the leakage at the joints in the external tension zone has greater effect on the internal forces of the structure compared with that of leakage at the joints in the inner tension zone, and the reduction value of water pressure at the joints, when a single joint is leaking, is greater than that of multi-joint leakage; for multi-joint leakage condition, the bending moments on the leaking side of the structure under leakage condition are greater than those on the non-leaking side, showing an obvious asymmetric distribution.
Abstract:
To address the problem of long-term operational safety degradation caused by water leakage in the joints of shield tunnels, this paper develops a numerical calculation model for joint leakage and analyzes the mechanical response of the segment structure with water leakage in the joints. The results show that water leakage in the joints could lead to a significant reduction in the external water pressure borne by the segments in the vicinity of the joints, and the reduction increases with the increase in the amount of leakage; the variation of internal force of the segment structure would experience three stages of rapid increase, slow increase and stabilization along with continuous leakage; a positive correlation exists between the magnitude of structural bending moments and axial forces and the amount of joint leakage; when the total leakage volume in the joints is the same, the leakage at the joints in the external tension zone has greater effect on the internal forces of the structure compared with that of leakage at the joints in the inner tension zone, and the reduction value of water pressure at the joints, when a single joint is leaking, is greater than that of multi-joint leakage; for multi-joint leakage condition, the bending moments on the leaking side of the structure under leakage condition are greater than those on the non-leaking side, showing an obvious asymmetric distribution.
SUN Zhihui TANG Yong LIU Tao
.The Influence of Partial Water Leakage on the Mechanical Properties of Shield Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(4): 141-149