天然电场选频法在水泥混凝土硬化面上的试验与应用  

Experiment and Application of Frequency Selection Method on Hardened Surface of Cement Concrete

作　　者：杨天春[1] 陈钰轩 梁竞 于熙 付国红[1] YANG Tianchun;CHEN Yuxuan;LIANG Jing;YU Xi;FU Guohong(School of Earth Sciences and Spatial Information Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Guangxi Guigang Engineering Geological Investigation Institute,Guangxi Zhuang Autonomous Region 273 Geological Brigade,Guigang 537101,China)

机构地区：[1]湖南科技大学地球科学与空间信息工程学院,湖南湘潭411201 [2]广西壮族自治区二七三地质队广西贵港工程地质勘察院,广西贵港537101

出　　处：《湖南科技大学学报（自然科学版）》2023年第4期30-36,共7页Journal of Hunan University of Science And Technology：Natural Science Edition

基　　金：国家自然科学基金资助项目(51804112)。

摘　　要：为弥补常规电阻率法在水泥硬化面的不适用性问题,通过试验和实践两方面探讨天然电场选频法在水泥混凝土硬化面上的有效性和适用性.首先,在野外选取两处存在水泥混凝土硬化面的试验地点,对硬化面上电极的接地方式进行改装,开展泥土和硬化面上3个频率(25,67,170 Hz)的选频法对比测试;其次,将该方法应用于广西贵港的城市地下水勘探中,根据实践效果来进一步论证天然电场选频法在城市水泥硬化面条件下的适用性.野外试验的2条对比测试剖面结果表明:在不考虑日变影响的情况下,电极插入土中与置于旁侧水泥混凝土硬化面上的探测结果一致,水泥硬化面对选频法的探测结果基本无影响.在贵港两处天然电场选频法找水的实践中,根据勘探结果均成功地打到地下水.实践表明:选频法可适用于城市一般的电磁干扰环境,在城市水泥混凝土硬化面上开展勘探工作是完全可行的,所得结果进一步拓宽了天然电场选频法的实践应用范围.The frequency selection method(FSM)of telluric current is a further development of the Audio-frequency Electrotellurics(AET)and the audio-frequency telluric field method.In this report,the applicability and effectiveness of FSM on the hardened surface of cement concrete were illustrated by experiments and practice,so that it could make up for the inapplicability of conventional resistivity method to the situation.Firstly,two test sites with hardened surface of cement concrete were selected in the field,and the electrode on hardened surface was modified,and comparative test of three frequencies(25,67 and 170 Hz)on soil and hardened surface were carried out.Secondly,the method was applied to the urban groundwater exploration in Guigang City,Guangxi Province,and the applicability of FSM under the condition of urban cement hardened surface was further demonstrated according to the practical effect.Two comparative test sections were obtained in field experiment.The test results show that the exploration results of electrode inserted into soil are consistent with it placed on the hardened surface of cement concrete.In other words,the hardened surface of cement concrete has no effect on the exploration results of FSM.According to the FSM exploration results in Guigang City,the groundwater has been successfully found in the two locations.The practice and experiment results show that FSM can adapt to the general electromagnetic interference environment in the city,and it is completely feasible to carry out exploration work on the hardened surface of urban cement concrete,which broadens the practical application scope of this method.

关 键 词：地球物理勘探 地下水 天然电场选频法 城市地球物理 电磁场 

分 类 号：P641.7[天文地球—地质矿产勘探]