Study on the Integrated Geophysic Methods and Application of Advanced Geological Detection for Complicated Tunnel

Abstract:

The engineering geological and hydrological conditions of current tunnels are more and more complicated, as the tunnels are elongated with deeper depth. In constructing these complicated tunnels, geological hazards prone to occur as induced by unfavorable geological bodies, such as fault zones, karst or hydrous structures, etc. The working emphasis and difficulty of the advanced geological exploration for complicated tunnels are mainly focused on the structure and water content of these unfavorable geological bodies. The technical aspects of my paper systematically studied the advanced geological exploration theory and application aspects for complicated tunnels, with discussion on the key technical points and useful conclusions.

For the all-aroundness and accuracy of advanced geological exploration results, the objective of my paper is targeted on the comprehensive examination on the structure and hydrous characteristic of the unfavorable geological bodies in complicated tunnels. By the multi-component seismic modeling on a more real model containing the air medium, the wave field response characteristics of unfavorable geological bodies can be analyzed, thus providing theoretical foundation for the observation system layout, signal processing and interpretation of seismic methods. Based on the tomographic imaging theory of seismic and electromagnetic method, 2D integrated seismic and electromagnetic tomographic imaging and visualization software was designed and applied in the advanced drilling hole in the tunnel face, after validation of the forward and inverse modeling results on theoretical models. The transmission wave imaging technology introduced in my paper can be served as a new criterion for detection of unfavorable geological bodies. After careful study on the basic theory, data processing and interpretation, practical applications of TSP and ground penetrating radar (GPR) method, as well as serious examination on their application examples, my paper formulated a suite of comprehensive application system of seismic and electromagnetic methods for the advanced geological exploration of complicated tunnels.

This research is funded by National Natural Science Foundation of China (Grant No. 41202223) .