In situ stress measurement and its application in the lOth Mine of Pingdingshan Coal Group

In situ stress measurements were carried out at 11 points of 6 levels in the 10th Mine owned by Pingdingshan Coal Group, using a three-dimensional (3D) overcoring stress measurement technique and hollow inclusion strain gages. The maximum measuring depth reaches 1123 m, and it is the first time to apply the overcoring technique to make systematical stress measurements with the measuring depth exceeding 1100 m at coal mines. 3D in-situ stress states at these 11 points were determined by the measurements. Based on measuring results, the regularities of in situ stress states in the mine were obtained and a mathematical model of regional stress field was also established. According to the high risk of coal (rock) bursts and gas explosion in deep mining of the coal mine, a method for predicting coal (rock) bursts was provided as follows. Based on numerical simulation and in situ measurement results, quantitative calculations are made of energy accumulation and its variation with mining process in the rock (coal) mass and surrounding rock, and then according to accumulated energy distribution, the seismology technology is used to predict the place, time and magnitude of coal (rock) bursting induced by future mining.