隧道地震不规则观测系统正演模拟与应用

结合隧道施工实际情况,提出了一种新的隧道地震不规则观测系统,利用该观测系统对隧道超前方向软弱夹层进行了正演模拟研究。研究表明:当炮数不变时,增加1个检波器可以明显改善偏移效果;当观测系统纵向偏移距越大时,偏移剖面画弧区域更小,当观测系统横向偏移距越大时,偏移剖面的镜像假像越弱。将该观测系统应用于重庆缙云山隧道,探测结果与开挖情况基本吻合,说明该观测系统合理可行。

Forward modeling and application of tunnel seismic irregular observation system

Combined with the actual situation of tunnel construction, a new irregular seismic observation system is proposed and used for forward modeling of the weak interlayer in the tunnel’s advance prospecting. The results show that when the number of shots is constant, adding one detector can notably improve the imaging; when the longitudinal offset of the observation system increase, the arc phenomenon in the imaging reduces; when the transversal offset increases, the mirror artifacts in the imaging weakens. The observation system was applied to the Jinyun Mountain tunnel in Chongqing, and the advance prospecting results were in good agreement with the excavation condition, indicating that the system is reasonable and feasible.