Vol14 No.6: 1124-1139
【Title】Interaction analyses between tunnel and landslide in mountain area
【Author】ZHANG Zhi-guo1,2,3,4*; ZHAO Qi-hua2; XU Chen3; XU Xiao-yang3
【Addresses】1 State Key Laboratory Breeding Base of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing 400074, China; 2 State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China; 3 School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China; 4 Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Land and Resources, Fuzhou 350002, China
【Citation】Zhang ZG, Zhao QH, Xu C, et al. (2017) Evaluation on interaction influences between tunnel and landslide in mountain area. Journal of Mountain Science 14(6). DOI: 10.1007/s11629-016-3999-y
【Abstract】This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the disturbance range induced by tunneling and the minimum safe distance between the tunnel vault and the sliding belt are obtained in consideration of the mechanical analyses of relaxed rocks over the tunnel opening. The influence factors for the minimum safe crossing distance are conducted, including the tunnel radius, the friction angle of surrounding rocks, the inclination angle of sliding belt, and the friction coefficient of surrounding rocks. Secondly, taking account of the compressive zone and relaxed rocks caused by tunneling, the Sarma method is employed to calculate the safety factor of landslide. Finally, the analytical solutions for interaction between the tunnel and the landslide are compared with a series of numerical simulations, considering the cases for different perpendicular distances between the tunnel vault and the sliding belt. Results show that the distance between the tunnel vault and the slip zone has significant influence on the rock stress and strain. For the case of the minimum crossing distance, a plastic zone in the landslide traversed by tunneling would be formed with rather large range, which seriously threatens the stability of landslide. This work demonstrates that the minimum safe crossing distance obtained from numerical simulation is in a good agreement with that calculated by the proposed analytical solutions.
【Keywords】Tunnel excavation; Landslide; Safe crossing distance; Analytical method; Numerical simulation