等值反磁通瞬变电磁法在浅层地质结构探测的应用

Application of equivalent antimagnetic flux transient electromagnetic method in shallow geological structure exploration

在复杂地质结构区域实施的工程建设,受气象环境、水文环境、地形地貌、地质构造等因素影响,岩土极易发生变形,严重时可能因受力过大而开裂,进而导致地基和建筑物发生变形,给建筑物带来安全隐患。因此,工程建设实施前,必须要充分掌握浅层地质结构变化情况与规律,从而为工程设计与工程施工提供全面准确的参考依据。等值反磁通瞬变电磁法是地下浅层地质结构探测的关键技术手段之一,该法采用双线圈源建立一次场零磁通接收平面来消除一次场对接收线圈的影响,以观测到地下纯二次场响应,从而提高瞬变电磁探测的准确度,缩小浅层盲区,达到精准探测地下地质变化情况与规律的目的。该方法具有野外工作简便快捷、不受施工场地限制及抗干扰能力强等特点,并通过工程应用证实探测精度和结果的可靠性,在工程地质勘察领域具有很好的应用前景。

Due to the influence of meteorological environment,hydrological environment,topography,geological structure and other factors,the engineering construction in the area of complex geological structure is very easy to deform,and may crack due to excessive stress in serious cases,which will lead to the deformation of the foundation and buildings,and bring potential safety hazards to the buildings.Therefore,before the implementation of the project,it is necessary to fully grasp the changes and laws of the shallow geological structure,so as to provide a comprehensive and accurate reference for the engineering design and construction.The equivalent antimagnetic transient electromagnetic method is one of the key technical means for the detection of underground shallow geological structure.In this method,the double coil source is used to establish a zero flux receiving plane of the primary field to eliminate the influence of the primary field on the receiving coil,so as to observe the response of the underground pure secondary field,so as to improve the accuracy of transient electromagnetic detection,reduce the blind area of shallow layer,and accurately detect the underground geological changes The purpose of the law.This method has the characteristics of simple and fast field work,no limitation of construction site and strong anti-interference ability.Through engineering application,it is proved that the detection accuracy and reliability of the results have a good application prospect in the field of engineering geological investigation.