Study on reason for differences of hydraulic conductivity of karst collapse columns in Wanbei Mining Area

In order to study the influencing factors of hydraulic conductivity of collapse columns, taking Liuqiao Coal Mine and Renlou Coal Mine as examples, com parison and analysis were carried out from three influencing factors, tectonic control, fllings characteristics of karst collapse columns and water pressure from Ordovici an limestone. The following conclusions were reached as follow: influenced by tectonic control, the runoff direction of groundwater supply to Liuqiao Coal Field from eas tern karst aquifer was changed by the Liuqiao Fault, and the karst collapse columns were affected by the disturbance of late structure; affected by FaultF2、F3、F16, t ectonic movement in Renlou Coal Mine made good groundwater run-off environment which was helpful to karst development. The flligs in karst collapse columns of Li uqiao Coal Mine had much greater proportion of mudstone and better consolidation than that of Renlou Coal Mine, so the water conductivity was more suppressed in Li uqiao Coal Mine than Renlou Coal Mine.Water pressure from Ordovician limestone of Liuqiao Coal Mine was lower than Renlou Coal Mine, and the capability of ground water seepage by overcoming the resistance of fllings in collapse column was lower in Liuqiao Coal Mine, so the range of seepage for the whole column was smaller.