(2) Carry out prediction and prediction of impact ground pressure. In order to comprehensively and accurately grasp the distribution status and risk degree of the impact pressure of the whole mine, regional and local predictions were made on the forecasting work. The prediction method uses a powder drilling method, an electromagnetic radiation method, and a mine pressure observation method.
(3) Increase the gas drainage capacity. In order to increase the amount of gas drainage, reduce the gas pressure, prevent gas explosion and coal and gas outburst accidents caused by impact pressure, the gas drainage system has been modified, and the mine gas drainage capacity has been increased from 350m3/min to 500 m3/min. Above, the gas extraction volatility increased from 75 million m3 in 1994 to 130 million m3 in 2001.
(4) Coal body water injection pressure relief. Starting from changing the physical and mechanical properties of the coal body, the coal body is subjected to static pressure and high pressure water injection to soften the coal body and relieve stress concentration to achieve the purpose of pressure relief.
(5) Leading pressure relief drilling. In the coal mining face with severe impact pressure, the advanced pressure relief drilling is carried out, and the operation of “two digging and one drilling†is adopted. That is, one small shift time is used to make 7 to 10 advanced pressure relief drill holes in one cycle per day. Arranged in the upper and lower rows, a row of holes is constructed every day, the hole depth is 10m, and the tunneling construction is carried out, so that the excavation work is carried out in the pressure relief ring, and the occurrence of impact pressure in front of the coal excavation face is eliminated.
(6) Deep hole pressure relief blasting. According to the impact of the ground pressure on the Hutai Coal Industry Branch, the main causes are the tectonic stress and the concentrated stress. In order to reduce the damage caused by the impact ground pressure on the roadway, the stress concentration area such as geological structure and coal pillar and the electromagnetic radiation value exceed the standard. The deep hole blasting pressure relief measures are adopted to slowly release the tectonic stress and the concentrated stress, thereby achieving the purpose of damping.
(7) Improve the equipment level of fully mechanized caving face. Improve the resistance of the working face bracket, the model is improved from the original ZFS4000-18/28 to ZFS6000-18/28, and the 68001# and 78001# fully mechanized caving surfaces have been subjected to multiple large impact pressures, but no crushing brackets have occurred. Phenomenon and accidents.
(8) Reform the roadway support method. To solve the problem of T iron shed behind the rigid support poor impact resistance, and has several times been on the roadway support reform in the form of a U-shaped steel retractable support, round bracket, bolting with wire mesh, mesh and anchor U-shaped bracket combined support, etc.; and in the roadway with severe impact ground pressure, the full-length anchoring support form is adopted, and the impact resistance effect is more obvious.
(9) Strengthen on-site safety protection. In order to reduce the damage caused by the impact of ground pressure, five safety protection measures for the prevention of impact ground pressure were formulated. The labor organization, the decentralized operation personnel, the number of restrictions and the operation time, and the idle equipment at the job site were promptly cleaned. The equipment and facilities were bundled and fixed, the U-shaped shed support shed distance, six U-shaped sheds for each U-shaped shed, and the long-term boring time (not less than 30 min) were successfully taken. Several times the large impact pressure.
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