Forecasting Study Of Water Disasters In Coal Mine Under Complicated Water Filling Condition

The text made a study of the forecast and prediction on the water burst of the third coal seam in Longgu coal mine. The paper combined the traditional research methods, such as "Down Three Zones" theory, "Up Three Zone" theory, water burst coefficient, and the current theories, such as tectonic fractal dimension, fuzzy clustering, multi-source information compound, and used various methods, such as qualitative analysis and quantitative evaluation combining, to make a study on several aquifers and compartmentalize water yield district, and predict the threat level of mining the third coal seam.The text made a detailed study of the terrane structure on the roof and floor of the third coal seam using sedimentology, geology, and other technical methods. On the whole, the lithology combination on the roof of the third coal seam in Shanxi formation is mainly sandstone containing shale, locally sandstone and shale interbedded, and the sandstone thickness emerge to the thick characteristic in center and north-east, and generally the sand-shale ratio is more than 1; the lithology combination on the roof of the third coal seam in Shanxi formation is mainly sandstone and shale interbedded, and the sandstone thickness show that the characteristics are thick in the south and thin in the north, thick in the west and thin in the east, and the sand-shale ratio changes slightly; the thickness characteristics of the third limestone are thick in the south and thin in the north, thick in the east and thin in the west. Water yield, which is on the roof and the floor of the third coal seam, lies on the thickness of sandstone and the sand-shale ratio. If the thickness of sandstone is more than 30m and the sand-shale ratio is more than 3, the water yield on the roof is well. If the thickness of sandstone is more than 40m and the sand-shale ratio is more than 1, the water yield on the floor is well. Water yield of the terrane is connected with the structure, particularly the tectonic faults. According to analyzing the fault characteristics and its distribution of the coal seam, using the method of cassette dimension to quantify structural indexes, the study show that the better condition to lead to water channel and water-rich space is that structural dimension is more than 2 and fractured connectivity is Strong. Based on analyzing the single-factors of water yield, such as the thickness of sandstone, sand-shale ratio, structural dimension, limestone thickness and its depth, using the principle and method of fuzzy clustering, the text standardized, demarcated and then classified the single-factors, and forecast the water yield of the sandstone on the roof and the floor of the third coal seam and the aquifer of the third limestone, and the water yield is divided into three levels, which are rich water yield, medium water yield and weak water yield; based on VB software empolder flat, the water disaster forecasting system of water inrush on the roof is established; using the function of MAPGIS multi-source information compound, through section space analysis, the text districted the dangerousness of water disaster on the floor, and divided into four levels, which are dangerous, less dangerous, less safe, safe; and proposed the programme of water disaster prevention and cure of the third coal seam in Longgu coal mine.