Face stability of shield tunnels considering a kinematically admissible velocity field of soil arching  

作　　者：Wei Li Chengping Zhang Dingli Zhang Zijian Ye Zhibiao Tan 

机构地区：[1]Key Laboratory for Urban Underground Engineering of the Ministry of Education,Beijing Jiaotong University,Beijing,100044,China [2]School of Civil Engineering,Beijing Jiaotong University,Beijing,100044,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2022年第2期505-526,共22页岩石力学与岩土工程学报（英文版）

基　　金：financial support provided by the National Natural Science Foundation of China(Grant No.51978042)。

摘　　要：Existing mechanism of simulating soil movement at tunnel face is generally based on the translational or rotational velocity field,which is,to some extent,different from the real soil movement in the arching zone.Numerical simulations are carried out first to investigate the characteristics of the velocity distribution at tunnel face and above tunnel vault.Then a new kinematically admissible velocity field is proposed to improve the description of the soil movement according to the results of the numerical simulation.Based on the proposed velocity field,an improved failure mechanism is constructed adopting the spatial discretization technique,which takes into account soil arching effect and plastic deformation within soil mass.Finally,the critical face pressure and the proposed mechanism are compared with the results of the numerical simulation,existing analytical studies and experimental tests to verify the accuracy and improvement of the presented method.The proposed mechanism can serve as an alternative approach for the face stability analysis.

关 键 词：Tunnel face stability Velocity field Failure pattern Improved failure mechanism Critical face pressure 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]