Stress evolution of surrounding rock and rock burst prevention technology of gob-side roadway in folded structural belt

Abstract

Aiming at the occurrence of rock burst along gob-side roadway in No.705 mining area of Baojishan Coal Mine, the occurrence mechanism of rock burst in folding structure is studied by means of field investigation, theoretical analysis, numerical simulation and field test. The results show that: 1# coal seam has strong impact tendency, and 1# coal roof and floor rock stratum has weak impact tendency. With the decrease of coal seam dip angle, the pressure on the lower side of gob increases, while the pressure on the upper side of gob decreases. The L-shaped stress concentration area appears on the solid coal side of gob at 30°. With the change of coal seam dip angle from 45° to 0°, the stress concentration is higher. Compared with the adjacent 703 working face, the coal seam dip angle of No.705 working face is reduced, and the degree of concentration in the coal seam is higher. Therefore, the increase of stress concentration in the fold structural belt is the internal factor. The technology of large diameter borehole combined with high pressure water injection and pressure relief and strengthening support cooperative control are proposed and applied in the field. The results of electromagnetic radiation monitoring show that the pressure relief and control effect is obvious.

Keywords

• rock burst
• inclination change
• gob-side roadway
• cooperative control
• electromagnetic radiation