Two-dimensional numerical simulation and characteristics analysis of seismic wave field based on a tunnel
Two-dimensional numerical simulation of seismic wave field based on a tunnel has an important guiding significance to understand the propagation law of seismic wave in tunnel advanced detection. All researches related to this subject are based on conventional observation system of TSP method and treat it as a homogeneous medium which has the same elastic parameters with the stratum in the front of the tunnel face. Moreover, they do not consider the numerical simulation and characteristics of seismic wave field when the geology interface dip angle is 90 degree, thus discrepancies exist from real conditions. Therefore, based on previous research results, this paper built geological model which is more similar to the practical tunnel situation, and adopts high order staggered-grid finite difference method with high calculation accuracy and efficiency to perform two-dimensional numerical simulation of seismic wave field. Simulation results show that: (1) when the geological interface is vertical(the inclination angle is 90 degree), exciting on the lateral wall of tunnel is not good for interface imaging, therefore, we should take the advantage of exciting on the tunnel face and acquire the reflection information of geological interface in the front of the tunnel face to accomplish the better interface imaging; (2) with the decreasing of geology interface inclination angle, exciting and receiving in downdip direction is favorable for data acquisition and imaging using TSP method; exciting on the position which is on the tunnel and close to the updip direction of geology interface, and receiving on the positions which are close to the downdip direction is good for S wave exploration; (3) no matter the interface inclination angle is 90 degree or not, using multi-component geophone can record enough information of the reflected wave of geology interface, and is good for multi-component joint tomography.
Jiangping Liu Niannian Qu Kerning Bu Cong Zhou
China University of Geosciences, Wuhan 430074, China China University of Geosciences, Wuhan 430074,China
国际会议
成都
英文
232-236
2010-06-14（万方平台首次上网日期，不代表论文的发表时间）