Tunnel Advanced Prediction Geophysical Method And Application Research

The Midwest area of China is mountainous. In large infrastructure constructionprojects, underground caverns and tunnels account for a large proportion, and more arethe control engineering. In the more complex areas of topography and geologicalstructure, where have fold belt, fault development, groundwater rich, and poorgeological conditions of surrounding rock. The collapse of roof fall, sudden gushingmud, lateral tunnel, the mountain crack, induced landslides, and other engineering andgeological diseases occur frequently in the tunnel construction process. To ensure thesafety of tunnel construction, quality, time and investment, advanced geologicalprediction in the tunnel has become an important link in the construction process.Geological prediction of tunnel is an international frontier subject, is also a difficultproblem, which are researched in the countries of world. To domestic and foreignresearch and application of the present general level, the advanced predictiontechnology is still evolving, many aspects need to study, improve and perfect.The results of this study are mainly the following aspects:1) Combining the advanced prediction method of the tunnel, numerical simulationwith experiment of forecasting, the existing forecasting techniques, especially the TSPforecasting techniques, are analyzed and summarized, which improve layout ofobserving systems, methods of data acquisition and data processing, extend itsapplication range, and increase the forecast accuracy.2) The seismic migration imaging technique and scattering imaging technique andits application to advanced prediction of tunnel, realizes high precision velocity analysisand high frequency energy spectrum imaging, combined with the characteristics ofgeological structure realizes the scanning direction, improves the forecast accuracy andreliability.3) Through research and experimentation of advanced prediction, the newforecasting concept is introduced, which proposes and applies to detection of theinternal and outside tunnel, seismic tectonic detection and electrical method combined with waterborne detection, geophysical exploration of combining with geologicalsurvey.This paper demonstrates the seismic reflection method is feasible in the advancedprediction of tunnel through the theoretical study and numerical simulation. Using thetunnel advanced prediction of seismic numerical simulation studies the characteristicsand the propagation law inside the medium of tunnels, and provides the theoretical andscientific basis for reasonable layout of the observing system, the right choice to receivethe sensor frequency, the exact identify of wave phase. Theoretical study andexperimental methods make a breakthrough of traditional concept at home and abroadby comprehensive prediction technology, improve the reliability and accuracy offorecasting, promote the improvement of domestic technology, and play a very positiverole in the promotion.