Multi-Scale Comprehensive Detection Technique to Identify Water Burst Causes in Karst Tunnels
(1 Ecological and Environmental Monitoring Center of Chongqing, Chongqing 401147; 2 China Coal Technology Engineering Group Chongqing Research Institute, Chongqing 400039)
Abstract：
Water inflows occur frequently during tunnel construction in water-rich Karst areas, thereby endanger? ing tunnel construction. Accurate and rapid analysis of water bursts are the premise of and key to water burst treatment. Based on the concept of multiple scales, a multi-scale comprehensive detection technique for identifying the causes of water bursts in karst tunnels is proposed, using the Huayingshan tunnel on the Yuguang expressway as an example. Based on hydrological dynamic observation data before and after water burst in light of the time scale, a comprehensive analysis is conducted from a point (working face) to a plane (area) in light of the spatial scale; it is determined that an interlayer fissure at 3.0-7.6 m in front of the working face connects the horizontal cyclic karst water within the elevation scope of +180 -+420 m, which causes water inflow in general water supply conditions. This conclusion provides a basis for the treatment measure of radial grouting after tunnel excavation.
2018, Vol. 55 