Study On Early Warning System Of Coal And Gas Outburst At Driving Face In Coal Road In Sihe Mine

China is one of the countries that mine and consume largest quantiy of coal in the world,with the rapid economic development, the energy is in greater and greater demand,the depth increases at a speed of almost 20 m/s, the ground stress and the gas pressure are getting larger and the coal mining geological and technological conditions are getting complex day by day. Coal and gas outburst is taking place in more and more mines, more and more frequently and strongly, so solving the problems on coal and gas outburst is on period. More than 70 percent of coal and gas outburst occour in the process of tunneling caol roadway, research on the occurring mechanism coal and gas outburst, it has a great theoretical and practical value to realize early warning to prevent from coal and gas outburst.In this paper, on the basis of analyzing the factors affecting coal and gas outburst, apply the theory analysis, experiment research, numerical simulation and monitor underground to realize scale warning of coal and gas outburst real-time. The main factors affecting the gas content are analyzed. Through analysis and comparison, according to the same degree on the trend of the isolines, the influences of each geological factor on the gas preservation are got, and then the contour map of the gas geological laws in Sihe Mine is given, analyzed the gas geological condition about caol and gas outburst taking plane in tunneling workface .Use FLAC3D software to building the three dimensional model of roadway tunneling, get the contour of mine disturbed stresss, the place of high stress zone and the largest stress, analyze the distribution of roadway stress in the process of tunneling and its influence to coal and gas outburst. Analyze the physical and mechanical properties and the permeability coefficient of each coal sample from Sihe Mine with experiment measure method. Such physical and mechanical characteristics as the deformation, strength and permeability of the coal samples are analyzed; with the data processing software (origin), the relationship among the permeability coefficient, the pore pressure coefficient and the volume stress is analyzed, which provides the fundamental basis for the study on the gas emission rule. Study on gas emission rule at driving faces ,the gas emission at the driving face is the aggregative indicator representing the stress state, the gas pressure state and the characteristics of the coal, which indicates the change situations of the ahead stress. Base on penetrability experiment and the analysis of the datas, analized the factors of gas emission in tunneling workface, gas consistency distribution in caol roadway tunneling workface and the gas emission rule in caol roadway in tunneling workface, completed the theory simulation method of gas emission volume in tunneling workface.A comprehensive evaluation on the moving average, amplitude, frequency and variance of the gas concentration series, then the identification model of the abnormal gas emission is established.Base on configuration software, develop software system for the real-time grading scale forewarning system of coal and gas outburst. Realized reading the real-time database of gas concentration monitoring at the workface, combined the exceptionally identified model, gas geological rule and mechanics model of coal roadway tunneling workface, realized scale forewarning the coal and gas outburst in coal roadway tunneling workface.