Comprehensive Outburst Prevention Technology for Opening 1 000 m Deep Depth and Special Thick Seam in Mine Shaft

In order to solve the seam opening outburst prevention and the seam passing construction safety in the mine shaft sinking with a depth of 1 000 m and u Itra thick seam, with the seven step method comprehensive outburst prevention technology, including the establishing regional outburst danger prediction, the permeabil ity improved gas drainage with deep borehole pre-crack controlled blasting, the effect inspection and verification, the middle hole bolt and metal frame, the seam openin g with long distance blasting, early warning of the outburst danger and the preset gas drainage borehole beyond the shaft liner, the construction safety was ensured fro m the technology, construction organization, project quality control and safety prevention. The results showed that with the reinforced measures of the deep borehole pr e-crack control blasting applied, the 41 days gas drainage operation could meet the regional gas outburst prevention requirements. With the grouting reinforcement with two circuit middle hole bolts and the preset one circuit gas drainage boreholes beyond the mine shaft liner and other new technology applied, the gas content during the seam opening and the shaft passing through the seam was very stable and the 9.8 m thick seam with a depth of 1 000 m was opened and was been passed through wit h no gas content over limit.