电阻率跨孔CT在城市地铁补勘岩溶探测下的工程验证

Engineering Validation of Resistivity Crosshole CT for Karst Detection in Urban Metro Supplementary Geological Investigation

摘要: 近年来，城市化进程加速推动了城市地铁建设规模扩张。首先需应对岩溶、溶蚀破碎带等不良地质体带来的风险。然而，城区施工环境复杂，人文活动及地下干扰源众多，导致常规物探方法探测地下岩溶时干扰显著。且部分特殊点位难以实施地质钻孔勘探，进一步增加了前期不良地质体勘探的难度。电阻率跨孔CT技术可在有限的钻孔条件下，有效探测地下岩溶分布及不良地质体，完成关键的前期勘探任务，其勘探结果能为盾构机选型及掘进方案的制定提供详实的地质依据，从而指导风险防控措施的提前部署。

Abstract: Recent accelerated urbanization has significantly expanded urban metro construction projects. Primary geological challenges involve mitigating risks from adverse formations, including karst cavities and dissolution fracture zones. However, the complex urban environment, with intensive anthropogenic activities and multiple subsurface interference sources, substantially compromises the effectiveness of conventional geophysical methods in detecting subsurface karst features. Furthermore, drilling feasibility constraints at critical locations exacerbate difficulties in preliminary geotechnical investigations. The resistivity crosshole CT technology enables effective detection of subsurface karst distributions and adverse geological formations under limited drilling conditions. This advanced method accomplishes critical preliminary exploration objectives, with its investigation results providing comprehensive geological references for both tunnel boring machine selection and tunneling scheme formulation, thereby facilitating proactive deployment of risk prevention and control measures.