综合物探方法在地铁孤石探测中的应用研究  

Application of integrated geophysical method to detection of boulder in subway shield zone

作　　者：赵东东 张宝松[1] 宗全兵 范福来 高伟 李路 许佳佳 ZHAO DongDong;ZHANG BaoSong;ZONG QuanBing;FAN FuLai;GAO Wei;LI Lu;XU JiaJia(Nanjing Center,China Geological Survey,Nanjing 210016,China;Fuzhou Metro Group Co.,Ltd.,Fuzhou 350000,China;Hunan 5D Geophyson Co.,Ltd.,Changsha 410205,China;Shanghai Civil Engineering Co.,Ltd.of Crec Urban Rail Transit Engineering Company,Shanghai 201906,China;China Railway NO.17 Bureau Group Sixth Engineering Co.,Ltd.,Fuzhou 350014,China)

机构地区：[1]中国地质调查局南京地质调查中心,南京210016 [2]福州地铁集团有限公司,福州350000 [3]湖南五维地质科技有限公司,长沙410205 [4]中铁上海工程局集团城市轨道交通工程分公司,上海201906 [5]中铁十七局集团第六工程有限公司,福州350014

出　　处：《地球物理学进展》2022年第3期1360-1370,共11页Progress in Geophysics

基　　金：中国地质调查局项目“福建省资源环境承载能力综合调查评价”(DD20190301);江苏省地质学会重点学术研究课题(JSDZXH-P2021-10)联合资助。

摘　　要：孤石是花岗岩不均匀风化所残留的风化核,具有空间分布不规律、埋藏深度不定、粒径不均等主要特征,给地铁盾构施工带来重大安全风险.在地铁工程建设中,孤石精准探测一直都是城市地铁盾构施工亟待解决的重要难题之一.本文针对以往单一物探方法探测孤石可靠性和精度相对较低,难以实现孤石体空间精准定位问题,提出一套孤石体精准定位物探方法组合探测技术,即以大深度探地雷达快速侦查孤石体的发育范围、微动法确定垂向边界、等值反磁通瞬变电磁法确定横向边界.福州地铁F1线葫芦山北侧的孤石探测应用示范结果表明:优选物探方法组合充分利用了三种方法之间可实现相互补充、相互验证的优势,有效避免了单方法存在多解性和干扰引起的假异常;结合已知地质和钻孔等资料校准了地层结构,实现了孤石体在三维空间的精准表达,对优化孤石探测技术、节约探测成本和实现无损、绿色勘查具有重要的意义.Boulder is the weathered core left by the uneven weathering of granite,and it has the main characteristics of irregular spatial distribution,uncertain burial depth and unequal particle size,which brings great safety risks to the construction of subway shield.In subway construction,the accurate detection of isolated stone has always been one of the important problems in shield construction of urban subway.The reliability and accuracy of the previous single geophysical exploration method for the detection of boulder is relatively low,and it is difficult to achieve the precise spatial positioning of the boulder.In this paper,a set of combined detection techniques for the precise positioning of the soliton body is proposed,that is,the development range of the soliton body is rapidly detected by the large-depth Ground-Penetrating Radar(GPR),the vertical boundary is determined by the Microtremor Survey Method(MSM),and the lateral boundary is determined by the Opposing Coils Transient Electromagnetic Method(OCTEM).The application demonstration results of isolated stone detection on the north side of Calabash Mountain of Fuzhou Metro F1 line show that:the optimal combination of geophysical exploration methods makes full use of the advantages of complementation and mutual verification among the three methods,and effectively avoids the false anomalies caused by multiple solutions and interference of a single method.Combined with the known geological and borehole data,the formation structure is calibrated to achieve the precise expression of the soliton body in the three-dimensional space,which is of great significance for optimizing the soliton detection technology,saving the detection cost,realizing the non-destructive and green exploration.

关 键 词：优选物探方法组合 孤石探测 大深度探地雷达 微动 等值反磁通瞬变电磁 

分 类 号：P631[天文地球—地质矿产勘探]