深孔控制卸压爆破防突机理和效果考察

MECHANISM AND RESULTS OF PREVENTION OF ROCKBURST BY CONTROLLED PRESSURE RELIEF DEEP HOLES

The paper proposes a new measure which can prevent locally outburst of rock and carbon dioxide, i.e. controlled pressure relief blasting of deep holes, on the basis of a summary of existing outburst control measures at home and abroad. The outburst process and conditions are analyzed by using stress wave and fracture mechanics. The outburst process can be divided into two stages. The paper points out that the key to prevention of outburst of rock and carbon dioxide is to stop formation of fractured zone and its propagation; and that the crack faces and compressed fractured zone produced by controlled blasting of deep blast holes for pressure relief can inhibit propagation of cracks and prevent the outburst and can prevent or inhibit the occurrence of outburst. The site tests have proved that this method is simple in technology, is good in prevention of outburst and is easy to popularize.