Study on Comparison of Methods to Determine Gas Drainage Radius and Existed Problems

In order to rapidly and effectively eliminate the outburst danger of the mining and excavation faces,the paper stated each method to determine the gas dr ainage radius,pointed out the problems existed in the determination of the gas drainage radius and had an outlook on the further study to determine the gas drainage ra dius.The study results showed that the gas drainage radius measures at site had high measuring difficulty and poor accuracy.The measured results were only the interv al value and other problems. The gas drainage radius measured could not be dynamically varied with the gas geological conditions.The gas drainage radius determined with the numerical simulation method had not considered the rheology features of the gas content coal and the effective gas drainage time determined had a high error. A further study on the liquid and solid coupling during the drainage process should consider the rhealogy features of the gas content coal to determine the rational gas drainage radius and to provide the basis for the gas disaster prevention and control.