OCTEM和TSP在铁路隧道超前地质预报中的联合应用  

Combined Application of OCTEM and TSP in Geological Prospecting of Railway Tunnel

作　　者：甄大勇 张硕 周超[1] ZHEN Dayong;ZHANG Shuo;ZHOU Chao(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu Sichuan 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,四川成都610031

出　　处：《中国铁路》2023年第10期60-67,共8页China Railway

摘　　要：查清铁路隧道轴线上的地质构造情况、降低隧道施工过程中地质灾害发生的几率和危害程度,已成为隧道建设的重中之重。首次将等值反磁通瞬变电磁法(OCTEM)和地震波反射法(TSP)2种物探方法相结合应用于某在建铁路隧道的勘察,通过在隧道掌子面开展TSP法查清构造大致位置,然后运用OCTEM法在地表进一步查明隧道轴线上地质构造的空间分布情况,利用OCTEM法得到的相对电阻率值和TSP法得到的掌子面前方围岩各项岩石力学参数,综合对比分析掌子面前方的地质情况,圈定出断层破碎带的厚度和范围,判定隧道前方洞身的围岩完整性和富水情况。将综合分析结果与掌子面实际开挖情况进行对比,结果表明:在地质构造走向与隧道轴线夹角较小的情况下,2种方法相结合能够准确地查清隧道施工作业前方地质构造的分布情况,更好地解决复杂的地质问题,为优化隧道工程设计及施工方案提供基础资料。It has become the top priority of tunnel construction to find out the geological structure on the axis of railway tunnel and reduce the probability and hazard degree of geological disasters during tunnel construction.Two geophysical prospecting methods,Opposingcoils Transient Electromagnetics(OCTEM)and TunnelSeismic Prediction(TSP),are applied during the investigation of a railway tunnel under construction for the first time.The approximate location of the structure is identified by TSP method on the tunnel face,and then the spatial distribution of geological structures on the tunnel axis is further ascertained by OCTEM method on the surface.The relative resistivity value obtained by OCTEM method and various rock mechanics parameters of surrounding rock in front of the tunnel face obtained by TSP method are used.The geological conditions in front of the tunnel face are comprehensively compared and analyzed,the thickness and scope of the fault fracture zone are delineated,and the integrity and water abundance of the surrounding rock of the tunnel trunk in front of the tunnel are determined.By comparing the comprehensive analysis results with the actual excavation conditions of the tunnel face,the results show that when the included angle between the geological structure strike and the tunnel axis is small,the combination of the two methods can accurately delineate the distribution of geological structures in front of the tunnel construction operation,better solve complex geological problems,and provide basic data for tunnel optimization engineering design and method statement.

关 键 词：OCTEM TSP 铁路隧道 超前地质预报 相对电阻率 岩石力学参数 

分 类 号：U456[建筑科学—桥梁与隧道工程]