Coal mine steeply-inclined coal seam large-section open-off cut pitching rock burst prevention and control method

Abstract

The invention discloses a coal mine steeply-inclined coal seam large-section open-off cut pitching rock burst prevention and control method. The method comprises the steps that a mechanical property of a top plate is changed through blasting, energy gathered by the top plate is released, and therefore, rock burst is prevented and controlled. The method is characterized in that the mechanical property of the top plate is changed through blasting, the locally gathered energy is transferred and released, and rock burst is prevented. For elastic energy gathered in a coal seam bottom plate, deep hole blasting is carried out on the coal seam bottom plate where an open-off cut is located, the elastic energy accumulated in a bottom plate rock stratum is transferred, the strength and the impact ofthe bottom plate during pressing are further reduced, a space-time influence relation of the stress state of the surrounding rock of the open-off cut is analyzed according to field tests and engineering analogy, it is guaranteed that the open-off cut is constructed in a pressure relief protection belt all the time, construction of the large-section open-off cut is improved, frequency and strengthof open-off cut blasting sound are effectively reduced, and safe tunneling of the large-section open-off cut is guaranteed.

Description

technical field [0001] The invention relates to a method for preventing and controlling rockburst in steeply inclined coal seam large-section cutouts in coal mines, relating to a method for preventing and controlling rockburst in large-section cutouts in steeply inclined coal seams, and belongs to the technical field of coal mines. In particular, it relates to a prevention and control method for preventing rock burst by changing the mechanical properties of the roof and the bottom plate through blasting, transferring and releasing the energy accumulated in the roof plate. Background technique [0002] The Wangjiashan coal mining area is located on the north side of the middle section of the Wushaoling-Leigongshan-Liupanshan fold belt in the main fold belt of the Longxi System. There are complex factors such as the early structure being cut and utilized by the late structure, thus forming a complex structural pattern in the Wangjiashan coal mining area, which is mainly prone ...

AI Technical Summary

Problems solved by technology

[0004] Wangjiashan Coal Mine’s previous large-section cut-outs in fully-mechanized caving faces with large dip angles were excavated from bottom to top. Due to the large inclination angle of the coal seam, the pressure on the front of the tunneling head was high during the construction process, and the roadway was prone to fall and pull out. The maintenance causes serious waste of materials and seriously affects the efficiency of enterprises.

[0005] Because the mechanism of rock burst, a new type of disaster in coal mines, is relatively complicated, there is no complete method that can be applied. It can only reduce and partially eliminate the hazards of rock burst, but cannot completely eradicate rock burst. In many places across the country, similar to the Wangjiashan coal mine Such coal mines with steeply inclined coal seams and large-section cut-outs are faced with the new disaster of rock burst, so the construction of large-section cut-outs in steeply inclined coal seams nationwide requires corresponding anti-scour technical support

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