基于共轴偶极装置的瞬变电磁超前地质预报方法与应用  

Advanced Geological Prediction Method and Application of TEM Based on Coaxial Dipole Device

作　　者：史存焕 刘黎东 贾祥雨 Shi Cunhuan;Liu Lidong;Jia Xiangyu(China Railway Liuyuan Group Co.,Ltd.,Tianjin 300308,China)

机构地区：[1]中铁第六勘察设计院集团有限公司,天津300308

出　　处：《工程地球物理学报》2021年第5期579-588,共10页Chinese Journal of Engineering Geophysics

摘　　要：针对隧道小回线瞬变电磁超前探测互感严重的问题,本文提出共轴偶极的瞬变电磁装置方法进行隧道超前地质预报。首先,对该装置的施工方法和原理进行了阐述,并采用三维有限元正演方法,建立了全空间隧道不良地水体病害模型,计算了掌子面前方测量时中心点的感应电动势和视电阻率,计算结果与所建模型的反映一致,说明该方法的可行性。接着,通过对比共轴偶极装置瞬变电磁法与TSP法、地质雷达法在超前地质预报的应用效果,以及用实际开挖揭示情况对共轴偶极瞬变法探测效果进行验证。结果表明:共轴偶极瞬变电磁法在隧道超前地质预报中具有一定的优势,可减小多匝线圈的互感效应,应用效果和其他两种结果基本一致,可进一步在铁路隧道超前地质预报中进行推广应用。In view of the serious mutual inductance problem of transient electromagnetic advanced detection in tunnel using the small loop.In this paper,we puts forward the transient electromagnetic device with coaxial dipole for tunnel advanced geological prediction.First of all,the construction method and principle of the device are expounded,and using the three-dimensional finite element forward modeling method,the whole space tunnel to poor water disease model was established,induction electromotive force and the apparent resistivity in the central point of loop were measured and calculated,the calculation results are consistent with the forward model.It illustrates the feasibility of this method.Then,the application effects of the transient electromagnetic method of the coaxial dipole device,TSP method and geological radar method in advance geological prediction were compared,and the detection effects of the coaxial dipole transient method were verified by the actual excavation.The results show that the coaxial dipole TEM has certain advantages in the advanced geological prediction of railway tunnels,and can reduce the mutual inductance effect of multi-turn coils.The application effect is basically consistent with the other two methods,and can be further applied in the advanced geological prediction of railway tunnels.

关 键 词：共轴偶极装置 瞬变电磁法 多方位 超前地质预报 反演 

分 类 号：P631.4[天文地球—地质矿产勘探]