Risk Assessment Of Water Inrush From Limestone In Eastern Mining Area Of Kongzhuang Mine Based On FAHP-CRITIC

Mine water disaster has always been one of the chief culprits of endangering the normal production of coal mines and water inrush from coal seam floor is the most common.That paper takes the 4 limestone of Taiyuan group of NO.7coal seam floor of eastern mining area in Kongzhuang Coal Mine as research objects,taking Piper trilinear monograph and Schoeller graph to analyses water chemistry characters of each aquifer;taking hole leakage rate and 4 limestone aquifer isopiestic line to analyses the law of karst development and the law of hydrodynamic force of 4 limestone of study area;using FAHP-CRITIC with modified game theory to build vulnerability evaluation model and establishing zoning map of vulnerability assessment of water inrush from the NO.7 coal seam floor.The main conclusions are as follow:?1?The study area belongs to the North China type Carboniferous Permian coal bearing strata.The faults in the area are mainly distributed in parallel,and tend to be consistent.The main faults are Xuzhuang fault,Xu branch fault,KF13fault,F_6-2 fault and F_6-6 fault.?2?The 4 limestone aquifer,whose water rich is not equal and with great changement in water level is easy to accept the infiltration and recharge of shallow aquifers,and is one of the main sources of water;Dissolution degree of 4 limestone is weaken as the depth increases;The water level of 4 limestone aquifer shows that the west is higher than the east on the whole,and only in some area of eastern mining area in Kongzhuang Coal Mine,the north is higher than the south;Most ions concentration variation coefficient of 4 limestone is relatively large,which means4 limestone has a certain connection with the outside aquifer.?3?The zoning map of vulnerability assessment of the NO.7 coal seam floor indicates that:The vulnerable area of water inrush is mainly distributed in the central and northern parts of the study area,accounting for 22.5%of the total study area.The less vulnerable area of water inrush is mainly distributed in the central,eastern and northern parts of the study area,accounting for 25%of the total study area;The transition area of water inrush is mainly distributed in the northwestern,central,southern and eastern parts of the study area,accounting for 25%of the total study area;The less safety area of water inrush is mainly distributed in the western and central parts of the study area,accounting for 15%of the total study area;The relatively safety area of water inrush is mainly distributed in the southwestern parts of the study area,accounting for 12.5%of the total study area;The assessment model is verified by Vulnerability Fitting Percentage,and the fitting rate is 100%,which turns out that vulnerability assessment model of water inrush from the 4limestone of Taiyuan group of NO.7coal seam floor is credible.The comparison of vulnerability index method with water inrush coefficient method used to evaluate the risk of water inrush of coal seam floor indicates that the vulnerability index method is with more comprehensive consideration of factors affecting water inrush of coal seam floor,and more realistic and instructive.