Abstract Because of different mechanical parameters such as stiffness and mass density, rock and soil may have different seismic responses in the interface area of a tunnel project, thereby causing serious damage to the tunnel structure. Based on a theoretical analysis and numerical simulation of the Qingdao subsea tunnel, the seismic failure mechanism and related aseismic measures of the tunnel structure at the rock-soil interface area were studied. The results show that rock failure, great seismic inertia forces induced by ground motion, and deformation caused by a large magnitude bedrock surface wave may result in damage to the tunnel linings in the rock-soil interface area, of which the last factor is the main cause; the damage to the tunnel structure can be prevented in the rock-soil interface area if the surrounding rock is kept stable and the differences in the mass density and stiffness between the tunnel structure and surrounding rock are minimized, the latter of which has proved to be the most effective; and a tunnel structure with light support and ductility has better seismic behavior. The results can be used as a reference for the study of seismic failure mechanisms and for the optimization of seismic design regarding tunnel structures within the rock-soil interface area.
Abstract：
Because of different mechanical parameters such as stiffness and mass density, rock and soil may have different seismic responses in the interface area of a tunnel project, thereby causing serious damage to the tunnel structure. Based on a theoretical analysis and numerical simulation of the Qingdao subsea tunnel, the seismic failure mechanism and related aseismic measures of the tunnel structure at the rock-soil interface area were studied. The results show that rock failure, great seismic inertia forces induced by ground motion, and deformation caused by a large magnitude bedrock surface wave may result in damage to the tunnel linings in the rock-soil interface area, of which the last factor is the main cause; the damage to the tunnel structure can be prevented in the rock-soil interface area if the surrounding rock is kept stable and the differences in the mass density and stiffness between the tunnel structure and surrounding rock are minimized, the latter of which has proved to be the most effective; and a tunnel structure with light support and ductility has better seismic behavior. The results can be used as a reference for the study of seismic failure mechanisms and for the optimization of seismic design regarding tunnel structures within the rock-soil interface area.
.Analysis and Study of the Seismic Failure Mechanism and Aseismic
Measures of a Tunnel Structure in the Rock-Soil Interface Area[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(4): 84-91
2013, Vol. 50 