基于FLAC3D的岩溶土洞演化及数值模拟分析

Evolution and numerical simulation of Karst caves based on FLAC3 D

以栖霞市中桥地区岩溶塌陷为研究对象,结合野外钻探、岩矿试验的地质、工程地质资料,采用FLAC3 D软件对"粉质粘土+透水土层+粉质粘土+灰岩"型岩溶塌陷模式进行模拟,通过对地下水位下降过程模拟、土洞开口大小及临界致塌水位降幅的确定,最终得出覆盖层25 m情景下,临界土洞最大安全高度为3.5 m,水位降幅1.20 m。岩溶区土洞的演化及数值模拟分析对于岩溶塌陷预报预警有着重要的理论意义,为保障人民财产安全提供依据。

Taking Karst collapse in Zhongqiao area of Qixia City as the research object,combined with the geological and engineering Geological data of field drilling and rock testing,FLAC3 D software was used to simulate the Karst collapse model of " powder clay + soil layer + powder clay + gray rock",Through the simulation of the water table descent process,the size of the earth hole opening and the reduction of the critical collapse water level,it is finally concluded that the maximum safety height of the critical earth hole is 3. 5 m and the water level decreases by 1. 20 m under the cover layer 25 m. The evolution and numerical simulation of soil caves in Karst area are of great theoretical significance to the prediction and early warning of Karst collapse,and provide evidence for the safety of people’s property.