Abstract:

Influenced by the pumping of groundwater in Jinshazhou tunnel of Wuhan to Guangzhou High-speed Railway, some large-scale karst collapses and ground subsidences had happened in Jinshazhou of Guangzhou during July 2007 to May 2012, causing serious damages on the economy. For preventing geological disasters, this study used methods such as general geological survey,groundwater monitoring, ground subsidence monitoring, drilling survey, physical detection to build a perfect groundwater and subsidence monitoring system. Based on that, according to the geological environment condition, the situation of karst development and distribution characteristics of geological disasters, the susceptibility of karst collapse of Jinshazhou was zoned.The variable quantity of underground water level and monitoring data of land subsidence which were the most directly sensitive and important parameters were utilized to study on how to select forecast parameters and time scales, to calculate discriminating parameters, to build forecasting method and forecasting model system. Combined with the 3D geological structure model, the comprehensive variable quantity of underground water level and the comprehensive land subsidence on critical day were selected as the discriminating parameter for predicting karst collapse to establish a warning and forecasting model system.This system was success fully employed to forecast two of karst collapses and achieved good results.It is revealed that the system for warning and forecasting karst collapses is useful and efficient and can provide anti-disaster science suggestions for Jinshazhou and technical supports for the local social stability and economic development.

Key words: karst collapse, geological disaster, critical day, underground water level, land subsidence, quantitative warning and forecasting