岩溶发育区地质勘察及岩溶精准探测技术

GEOLOGICAL SURVEY OF KARST DEVELOPED AREAS AND PRECISE KARST DETECTION TECHNOLOGY

为了确保盾构法在岩溶发育区隧道施工中顺利、安全、快速掘进,本次勘察在施工前试验了钻探(常规向下的钻芯及取样)及物探(采用地质雷达法、微动探测法、瞬变电磁法、跨孔CT法、管波和陆地声纳法等地表及洞内物探技术)相结合的综合勘察方法,各探测方法间相互多次验证并综合工程数据实际进行推断和结果分析处理,最终选择用微动、陆地声纳法结合跨孔CT准确探测了大小1 m及以上的溶洞及溶蚀裂隙、含水构造等,探明了岩溶发育区等不良地质的岩土分界线、厚度及埋深等情况,基本上将线路沿线全部溶洞的大小规模、发育情况和与隧道洞身的相互位置关系都探明清楚并分析得到了一系列成果数据。

In order to ensure the smooth,safe and rapid excavation of the tunnel construction in the karst zone by the shield method,in this survey,a comprehensive survey method combining drilling(conventional downward drilling and sampling)and geophysical prospecting(using geological radar method,micro-motion detection method,transient electromagnetic method,cross-hole CT method,tube wave and land sonar method and other geophysical exploration techniques for the surface and cave)was tested before construction.The detection methods have been verified multiple times with each other and the actual engineering data is integrated for inference and result analysis and processing.Finally,the micro-motion,land sonar method and cross-hole CT are used to accurately detect caves,dissolution fissures,and water-bearing structures with a size of 1 m and above.The geotechnical boundary,thickness,and depth of the rock and soil of the karst development zone and other unfavorable geology have been proved.Basically,the size and development of all caves along the line and the mutual positional relationship with the tunnel body are clearly ascertained and a series of results data have been obtained.