Geophysical Methods Applied Research In The Geological Survey Of The Long Tunnel, Buried In The Yunnan Highway

In the construction of Yunnan highway, the deep-lying long tunnels is increasing day by day. The traditional engineering geological Investigation acquire geological data, by observing the surface geology to infer the deep geology and disposing some drilling to verified the deep geology, But the geological data acquired by the traditional engineering geological investigation is difficult to meet the need of deep-lying long tunnels. On the contrary, the geophysical methods can detect geophysical Field continuously and get a lot of geophysical information, it can finish the geological survey of the deep-lying long tunnels more quickly economically. About 20 years'tunnels exploration data have been collected by Highway planning, survey and design institute of Yunnan province, but the data have not been studied systematically. The paper want to conclude a quick and efficient geophysical methods, through studying tunnels exploration data, to enhance the tunnel geological survey quality, shorten the exploration cycle, save on expense.To consider from the exploration depth of geophysical methods and the effectiveness in the application of the tunnel exploration, I study the application of the geological method in deep-lying long tunnels, by choosing the electrical sounding method, TEM, CSAMT, EH4, seismic refraction method and seismic reflection method in this paper.First of all, I analyse whether the geophysical methods can be applied to the exploration of formation lithology, geological structure, groundwater, and surrounding rock classification in deep-lying long tunnels from a theoretical point. through summarizing the common geophysical characteristics(electrical resistivity and seismic P-wave velocity) and the characteristic of abnormal response of formation lithology, geological structure, groundwater, and Surrounding Rock Classification, and analysising the main factors on geophysical methods, I concluded that most geological problems in deep-lying long tunnels can be solved by geophysical methods, although the results of geophysical observations can be interfered by many factors, but most interference can be overcome, geophysical methods can be unusually effective.And then I select six typical examples about the tunnel exploration to analysis the effectiveness of the electrical sounding method, TEM, CSAMT, EH4, seismic refraction method and seismic reflection method in the exploration of formation lithology, geological structure, groundwater, and Surrounding Rock Classification in deep-lying long tunnels. The prospecting effect show that the electrical sounding method, TEM, CSAMT, EH4, seismic refraction method and seismic reflection method can solve the most problems of formation lithology, geological structure, groundwater, and Surrounding Rock Classification in deep-lying long tunnels.Through the application of the feasibility study and case analysis, combined with the knowledge acquired form about 20 tunnels exploration data, I sum up the effective geophysical method and the effective method of field work, data processing and interpretation in the exploration of formation lithology, geological structure, groundwater, and Surrounding Rock Classification in deep-lying long tunnels.