Analaysis of Deformation and Its Control Measures for Large-diameter Shield Tunnels Passing under Building Complexes
(1. Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai 200092; 2. Shanghai Municipal Engineering Design Institute (Group) Co., Ltd., Shanghai 200092)
Abstract:
The excavation construction of large-diameter shield tunnels would cause disturbance to the soils, result? ing in ground settlement or heave, and thus bringing serious threats to the structural safety of the building complexes above. Based on a large-diameter shield tunnel passing under a dense group of building complexes in an old neighborhood, this paper first calculates the settlement deformation of the houses on key sections through 2D finite element software, and then compares the calculation results with those through 3D finite element software to analyze the applicability of the two calculation methods. Subsequently, on the basis of the 3D model, it studies the effects of different initial load release rates on the ground surface and house deformation caused by the shield tunnel construction. Finally, by using the theoretical ground settlement data calculated by the Peck formula, it sorts out the internal correlation among the initial load release rate, the ground settlement, and the ground loss rate, and puts forward relevant measures to control deformation. The research results show that the smaller the initial load release rate is, the smaller the ground surface and house settlement as well as corresponding ground loss will be. In terms of ground deformation control, the reduction of the load release rate is equivalent to decreasing the ground loss rate, and the decreasing amounts of initial load release rate, ground settlement, and ground loss rate are in a linear correlation.
SUN Shuangchi1,
2 SHEN Yi1 ZHOU Zhiyan2 ZHOU Long1 ZHU Hehua1
.Analaysis of Deformation and Its Control Measures for Large-diameter Shield Tunnels Passing under Building Complexes[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(2): 103-110