Study On The Upper Mining Limit Under Drained Quaternary Water-Bearing Stratum In Taiping Coal Mining

Extending the upper extraction limit by draining bottom water of Quaternary is one of the efficient method, with safety and sufficiency of mining. On considering the multi-aspects-crossing of hydrogeology, engineering geology, during mining subsidence, investigation engineering, mining engineering and etc., the engineering geological condition of overburden is analysed and an engineering geology model is established at first basing on the drilling, geophysical exploration and other data from Taiping coal mine. Next, the test of geology mechanical model is carried out to simulate the condition of workface 8301. the test revels the rules of overburden failure during mining, from which the height of failure zone and safety degree of that are decided in the overburden adjacent to the zone of weathering. What's more, the technology of draining the difficult-drainage layer is discussed basing the analyzing of hydrogeological condition and mining examples civil/alien by means of drainage, and also the safety hydraulic head to prevent water or sand inrush of different soil layers above the failure zone is deduced. At last, all the results have been confirmed by measurement during mining and the practice is succeed.