Effect of a Fault Fracture Zone on the Stability of Tunnel-Surrounding Rock

摘要

Abstract>The fault fracture zone is vital to the stability of the surrounding rock of tunnels in geological engineering. In this study, a three-dimensional numerical model was established for Wuzhuling Tunnel of Zhuji-Yongjia Highway in Zhejiang Province, China. The dynamic processes of tunnel excavation were simulated through the fault fracture zone. The deforming performance and stress distribution of surrounding rock were investigated. Moreover, the stability of surrounding rock in tunnels was analyzed with consideration of the slope angle and the width of the fault. The simulation results indicate that the fault fracture zone in the tunnel can reduce the stability of surrounding rock. The slope angle and the width of the fault all have obvious influences on the stability of surrounding rock in tunnels. Furthermore, the collapse processes of a tunnel in the construction steps were investigated in a laboratory model. Reasonable agreements can be obtained to validate the model presented here and the simulation results. When excavating tunnels in a fault fracture zone, numerical analysis can be performed to find the dangerous area at which collapse might occur easily. This study can provide useful information on a supporting structure to prevent collapse disaster when designing a tunnel.]]>