标题：Comparison of transient electromagnetic configuration in prediction of water bearing structures in tunnels
作者：Li, Kai ;Sun, Huaifeng ;Su, Chuanxi ;Li, Shucai ;Tang, Pengyue ;Qi, Zhipeng
作者机构：[Li, Kai ;Sun, Huaifeng ;Su, Chuanxi ;Li, Shucai ;Tang, Pengyue ] Geotechnical and Structural Engineering Research Center, Shandong University, Ji'nan 更多
来源：Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering
关键词：Apparent resistivity; TEM configuration; Transient electromagnetic; Tunnelling engineering; Water-bearing structure
摘要：In order to study the influence of different configurations on the acquisition data and imaging quality in the tunnel transient electromagnetic(TEM) detection, four configurations, which contain central loop and three different dipole-dipole(fixed transmitting line moving receiver, fixed transmitting arch moving receiver, fixed transmitting loop and receiver distance), are researched by numerical and field experiments. In numerical test, both vertical and titled water filled fault models are studied using 3D finite difference time domain(FDTD) method, and electromagnetic response is analyzed and researched. In field test, a known experimental site in hydropower station is used to collect electromagnetic field data. Numerical and field test data utilize full-time apparent resistivity calculation method to image the apparent resistivity. The numerical and field test found that four configurations can locate the water position, but different configuration has different phenomenon. Firstly, the fixed transmitting line moving Receiver dipole configuration is most effective to identify the position and shape of water filled fault; Secondly, the central loop configuration can effectively identify the location but not good at recognizing the shape; Thirdly, the fixed transmitting loop and receiver distance dipole configuration is good at recognizing the shape but not good at finding the location; Lastly, the fixed transmitting arch moving receiver dipole configuration cannot effectively identify the location and shape. All in all, the fixed transmitting line moving receiver dipole configuration is the most effective method to identify the location and shape of water filled faults in tunnel detection of TEM, and transmitting loop is fixed on the tunnel face, we just move the receiver to improve work efficiency. © 2017, Science Press. All right reserved.