Abstract:
An increasing number of coal mines will focus their operations on the coal seams present in the early Carboniferous Taiyuan Group in North China.It is expected the risk of water inrush from the Ordovician confined limestone aquifer through the floor of overlying excavations to be significant during mining.The current study is using the No.162,163 district in Jiangzhuang coal mine,which is located in the Tengzhou coal field in the Shandong province,as an example of how to calculate and zone this risk based on the analysis of local geological and hydrogeological features such as hydraulic pressure and water yield capacity of the limestone aquifer,fault density,fault crossing and endpoint density,scale index of faults,and effective aquiclude thickness.The vulnerability index was determined using Geographical Information Systems and Analytic Hierarchy Process techniques in order to build the risk prediction model.Four areas were identified with the prediction model based on the risk of water inflow to the floor of the coal seam:safe,transitional,less dangerous,and dangerous.The model validation was carried out by using actual data from the No.16301 workface and showed that it predicted the water inflow risk better than the traditional water inrush coefficient method.The model was considered to be accurate and therefore reliable and helped with the policy to prevent and control groundwater hazards during the mining of coal seam No.16.