THE APPLICATION OF TSP24SYSTEM IN PREDICTION OF TUNNEL GEOLOGIC HAZARDS

This article describes the principle of TSP24 advanced detection systems and its application in advanced geological forecasting.We laid TSP24 system in a tunnel in Shanxi province and obtained detection data.We extracted the reflected wave on geological interface in front of the working face using wave field separation method and created the three-dimensional image of the geological interface using ray tracing, velocity scanning and Kichihoff migration imaging method.The results indicate that:(1)the elastic wave velocity of rock decrease obviously, energy of the reflected wave in depth migration image is strong, and the velocity of surrounding rock changes greatly;(2)in shear wave migration image, energy of the reflected wave is strong and reflection interfaces are widely distributed, this may indicate that the rock in this section is broken seriously, fractures are widely distributed.The surrounding rock is not stable and eases to crush, mean while, higher water contents of rock may lead to water gushing.Treatment measures were taken during the excavation process and effectively avoided water inrush accidents.