摘要
在提出电磁勘探法探测堤坝管涌渗漏隐患的基础上,对其可行性进行了理论分析和论证。首先分析了计算水平、电性均匀大地的情况下,半方形直流供电装置的线电流和体电流的磁场分布特征,然后讨论了管涌通道有无露头条件下,管涌有集中电流流过时在地表所产生的磁感应强度,并分析了磁场沿剖面的变化情况。结果表明:如果合理布设供电电极和电缆,就能减小供电装置的线电流与体电流组合磁场在勘探剖面上的强度,而管涌通道所产生的磁场是供电装置本身组合磁场的几倍甚至十几倍,并且其异常值的大小很容易被高精度磁力仪探测出来;同时,二者的磁场变化规律明显不同,采用直流电供电与高精度磁测相结合的方法可探测堤坝管涌渗漏隐患。
On the basis of presenting the piping and seepage detection by electric-magnetic prospecting method,the paper analyzed and testified validity of the method.At first,magnetic field characteristics of linear current and body current were calculated and studied for half-quadrate setting of direct current in conditions of level and homogeneous electric half-space.Secondly,when the piping had an outcrop or had not outcrops,the magnetic field on the ground and its changes along sections were discussed when there was concentrative current flowing in the piping.According to calculated results,the magnitude of magnetic field of artificial current was smaller on section if electrodes and cables were set rationally.Usually,the magnetic field magnitude of piping had several times to more than decuple comparing with magnetic field of artificial current.So,the magnetic abnormity could be detected easily by high-precision magnetometers.At the same time,their curves＇ characteristics were different evidently,the piping and seepage of dyke can be detected by combining method of direct current supplying and high-precision magnetic survey.
出处
《人民黄河》
CAS
北大核心
2011年第10期14-17,共4页
Yellow River
关键词
电磁勘探法
高精度磁测
管涌
渗漏
堤坝
electric-magnetic prospecting method
high-precision magnetic survey
piping
seepage
dyke
