Study on Forces on Pipe Umbrella Support in the Whole Process of Tunnel Excavation
(1. State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian 116024; 2. Department of Engineering Mechanics,Dalian University of Technology, Dalian 116024; 3. China Railway Cloud Information Technology Co., Ltd., Beijing 101300; 4. Urban Rail of China Railway No.8 Engineering Group Co., Ltd., Chengdu 610037)
Abstract:
In order to investigate the mechanical behaviors of the pipe umbrella support system in the tunnel at the Hutan New Area Station of Dalian Metro Line 5, finite element simulation of the tunnel pipe umbrella support system has been conducted by using the Plaxis software, the mechanical behaviors of the pipe umbrella support in the whole process of tunnel excavation have been analyzed, the results of finite element simulation have been compared against the ground settlement and crown settlement observed on site, and simulation analysis for optimization of the pipe umbrella support parameters has been conducted. The calculation results suggest that in the whole process of tunnel excavation, the pipe umbrella deformation and stress show the stepped or wave-like variation pattern. Through comparative analysis on the changed design parameters of pipe umbrella, it is concluded that the pipe umbrella forces are significantly affected by soil stratum load, the axial force of pipe umbrella is mainly affected by the circumferential spacing of pipe umbrella, and also the bending moment and shear force are significantly affected by the pipe diam? eter. For subway tunnel construction, use of pipe umbrella support will ensure the works proceed successfully
JI Yunpeng1,
2 FANG Lingguo3 TANG Haotian4 ZHANG Xingli1,
2 WANG Xiangjin1 etc
.Study on Forces on Pipe Umbrella Support in the Whole Process of Tunnel Excavation[J] MODERN TUNNELLING TECHNOLOGY, 2023,V60(3): 123-138