黔中地区浅覆盖型岩溶塌陷成因机制与防治对策--以紫云县白云小学为例

黔中地区处于贵州省第二阶梯,平均海拔800~1600 m。具有可溶岩分布面积广、岩溶极其发育、第四系土层覆盖薄、地下水埋深浅、地下水动力条件强等特点。岩溶地面塌陷是该区主要地质灾害之一。为了查明贵州省紫云县白云小学岩溶塌陷的成因及发育机制,在塌陷区开展了水文地质调查、地球物理勘探、水文地质工程地质钻探、岩土样测试等多项工作。综合研究表明,白云小学岩溶塌陷是特殊的"水-土-岩"不良因素共同作用的产物。根据塌陷区的岩土组构特征,建议在黔中岩溶地区进行工程选址前,采用"监测预防+控水+工程治理"综合防治措施。

Study on the genesis mechanism and prevention and control measures of shallow overburden karst collapse in central Guizhou area: An example of Baiyun primary school, Ziyun county, Guizhou Province

Central Guizhou Province lies in the second topographic step of the plateau,with average altitudes 800-1，600 m,characterized by widely distributed soluble rocks,extremely developed karst landscapes,thin Quaternary soil layers and shallow groundwater with strong groundwater flow dynamics.Karst ground collapse is one of the major geological hazards in this area.In order to clarify the cause and mechanism of karst collapse in the Baiyun primary school,Ziyun county,Guizhou Province,this work carried out field investigations,geophysical exploration,geological drilling of hydrogeology engineering,and tests on rock and soil samples.Comprehensive research indicates that the karst collapse in the Baiyun primary school was a combined effect of special “water-soil-rock” adverse factors.According to the characteristics of geotechnical structure of the collapse area,it is suggested that the comprehensive prevention and control measures of "monitoring prevention+water control+engineering treatment" should be adopted before the site selection of future projects in karst areas of central Guizhou.