Abstract The rock mass dislocation in the large active strike-slip fault fracture zone exhibits significant nonlinear characteristics, resulting in varying failure features of rock and soil masses in different areas of the fault zone. This makes the deformation and stress of tunnel structure crossing fault zones increasingly complex. This paper, based on a tunnel project crossing a large strike-slip fault, uses model tests and numerical simulations to obtain the longitudinal distribution patterns of tunnel structure responses when crossing faults with multiple fracture surfaces. The results show that with the increase in fault dislocation, the horizontal displacement of the tunnel continuously increases,showing an S-shaped deformation pattern, with dislocation-induced deformation mainly occurring in the fault zone. Under strike-slip fault dislocation, the compression is more pronounced between the reverse bending concave section of longitudinal deformation curve of the tunnel arch waist and the surrounding rock, while the convex section has a tendency to detach from the surrounding rock. The stress-induced failure of the tunnel structure is mainly concentrated near the two fault dislocation surfaces, with the tunnel structure in the upper wall being more prone to failure compared to the lower wall.
Abstract:
The rock mass dislocation in the large active strike-slip fault fracture zone exhibits significant nonlinear characteristics, resulting in varying failure features of rock and soil masses in different areas of the fault zone. This makes the deformation and stress of tunnel structure crossing fault zones increasingly complex. This paper, based on a tunnel project crossing a large strike-slip fault, uses model tests and numerical simulations to obtain the longitudinal distribution patterns of tunnel structure responses when crossing faults with multiple fracture surfaces. The results show that with the increase in fault dislocation, the horizontal displacement of the tunnel continuously increases,showing an S-shaped deformation pattern, with dislocation-induced deformation mainly occurring in the fault zone. Under strike-slip fault dislocation, the compression is more pronounced between the reverse bending concave section of longitudinal deformation curve of the tunnel arch waist and the surrounding rock, while the convex section has a tendency to detach from the surrounding rock. The stress-induced failure of the tunnel structure is mainly concentrated near the two fault dislocation surfaces, with the tunnel structure in the upper wall being more prone to failure compared to the lower wall.
PAN Xiaohai1 SHEN Yusheng1 WANG Haokang1 WANG Yanyan1 ZHANG Xinyang1 ZHANG Xi1 ZUO Leibin2
.Study on Response Characteristics of the Tunnel Structure under Dislocation of Strike-slip Faults with Multiple Fracture Surfaces[J] MODERN TUNNELLING TECHNOLOGY, 2024,V61(4): 210-220