Study on the influence of lining structure on seismic stability of deep buried tunnel based on FDM-DEM

Abstract

Abstract Faults are prone to crack due to the influence of stratum dynamic load, and the research on the influence of different surrounding rock support schemes on load resistance is complicated. Based on the F2 fault in Tianshan, Xinjiang, this paper introduces the establishment of FDM-DEM coupling model and load application. The influence of anchor bolt support on the load resistance of secondary lining is studied by using the coupling model of Finite Difference Method (FDM) and Discrete Element Method (DEM) with different anchor bolt support schemes combined with dynamic and seismic loads. The results show that: (1) the increase of anchor bolt support length can effectively improve the dynamic load bearing capacity of surrounding rock. (2) Under earthquake load, the secondary lining is prone to collapse from arch waist to arch top and crack at arch foot. The effect of anchor bolt support on the internal force of secondary lining is less than that of anchor bolt support. (3) The internal force of secondary lining is mainly affected by load, and the increase of tension chain in secondary lining under dynamic load indicates that the secondary lining is mainly caused by tensile crack. This study provides an effective tool for the synthesis of seismic performance.