瞬变电磁法在岩溶地区地基勘察中的应用

The Application of TEM Method to Foundation Investigation in Karst Region

岩溶是工程建筑中频繁遇到的一种典型的地质灾害,它给工程建筑安全带来了极大的安全隐患。为了查明建筑地基岩溶分布及发育情况,受场地条件限制,常规物探方法基本不能开展工作。因此根据岩溶与围岩的电性差异特征,运用瞬变电磁法(TEM)对建筑场地岩溶发育区进行探测。实践证明,瞬变电磁法的应用对查明建筑场地内溶洞的分布范围、规模大小和埋深有良好的效果,能为后期勘察工作提供重要的参考价值及指导性意义。

Karst is a typical and frequent geological disaster in engineering construction and it brings great security hidden danger for engineering construction safety.In order to find out the Karst distribution and development of building foundation,the conventional geophysical prospecting method can hardly be carried out on account of the limitation of site condition.According to the differences of electrical properties between karst and surrounding rock,the transient electromagnetic method（TEM）is used to analyze the Karst development of building sites.Practice shows that the application of transient electromagnetic method has a good effect on finding out the distribution scope,size and burial depth of Karst cave in the construction site,which provides important reference value and guiding significance for the later investigation work.