Ground deformation of site with an exciting fault-crossing tunnel and deformation evaluation on tunnel subjected to normal faulting

Crossing-fault tunnel is vulnerable especially when the fault dislocation happens. The propagation of fault rupture affects the deformation on ground surface and failure on underground structures and it is vital for crossing-fault tunnel to reveal dislocation mechanism with fault rupture propagation. Thus, based on different fault parameters such as width of fault fracture zone and fault dip, three experimental tests were carried out to obtain the propagation mechanism of fault rupture and its impact on ground deformation and failure of tunnel with a self-designed large-scaled model box. The test results firstly show that the fault parameters effect the pattern of fault rupture. Under the propagation of fault rupture, four sub-regions were identified on ground surface as stability region in footwall, coordination region, severe deformation region and stability region in hanging wall. The parameter influence from fault fracture zone will be sensitive for tunnel and the tunnel near fault fracture zone is most damaged. Typical damage types transversely can be divided into four categories according to the degree of damage and moderate damage or serious damage should be avoided as far as possible to guarantee the normal operation of the tunnel.