The gas cooperative control model combined local pressure-relief with regional pressure-reliet was estaonsnea, based on the theory of multi-parameters cooperative. For the status of high gas contents, high in-situ str...The gas cooperative control model combined local pressure-relief with regional pressure-reliet was estaonsnea, based on the theory of multi-parameters cooperative. For the status of high gas contents, high in-situ stress and low-permeability of Ji-15 seam of No.12 coal mine in Pingmei Group. The law of detonation wave propagation and ground-stress change distribution were simulated by means of the finite element analysis software. The technology of high-low-blasting, composed of high blasting(deep crossing hole controlled hydraulic blasting) and low blasting (special roadway deep hole controlled blasting) were developed. The research shows that around control hole produce maximum tension fracture failure, and result in directional and controlled Masting, when the distance between control hole and blasting hole is 1.2 m. The theory makes blasting force and hydraulic force advantage superimpose, which raises the effect of pressure relief and permeability enhancements compared with general blasting. High blasting influence radius and low blasting influence radius superimposed with each other, that prevents methane dynamic disaster. The result of type approval test shows that the technology can increase gas permeability as high as 22.7-36.2 ratio, decrease gas pressure from 2.85 MPa to 0.30 MPa, increase drilling influence radius to about 9 m. The technology realizes regional overall permeability improvement, that provides a new technical measure for methane dynamic disaster prevention.展开更多
基金Supported by the Major Project of Chinese National Program for Fundamental Research and Development (973) (2011CB201205) the Nature Science Foundation of China (50804048)
文摘The gas cooperative control model combined local pressure-relief with regional pressure-reliet was estaonsnea, based on the theory of multi-parameters cooperative. For the status of high gas contents, high in-situ stress and low-permeability of Ji-15 seam of No.12 coal mine in Pingmei Group. The law of detonation wave propagation and ground-stress change distribution were simulated by means of the finite element analysis software. The technology of high-low-blasting, composed of high blasting(deep crossing hole controlled hydraulic blasting) and low blasting (special roadway deep hole controlled blasting) were developed. The research shows that around control hole produce maximum tension fracture failure, and result in directional and controlled Masting, when the distance between control hole and blasting hole is 1.2 m. The theory makes blasting force and hydraulic force advantage superimpose, which raises the effect of pressure relief and permeability enhancements compared with general blasting. High blasting influence radius and low blasting influence radius superimposed with each other, that prevents methane dynamic disaster. The result of type approval test shows that the technology can increase gas permeability as high as 22.7-36.2 ratio, decrease gas pressure from 2.85 MPa to 0.30 MPa, increase drilling influence radius to about 9 m. The technology realizes regional overall permeability improvement, that provides a new technical measure for methane dynamic disaster prevention.