Abstract: A method is to excavate main roadways in the upper and lower parts separately and an inclined intake roadway in the central part of the mine and pre-excavate an inclined seam roadway as the first mining face at the boundary on one side of the mine. Staring from the mine boundary, the retreating mining shall be carried out on the first mining face strip by strip with belt conveyors arranged in the upper main roadway and assistant conveying devices in the lower main roadway and inclined intake roadway; the open-off cut of the first mining face shall be built on the underside of the upper main roadway at the boundary of the mine to carry out the downward inclined mining on the strike and along the inclination.

Abstract: A method is to excavate main roadways in the upper and lower parts separately and an inclined intake roadway in the central part of the mine and pre-excavate an inclined seam roadway as the first mining face at the boundary on one side of the mine. Staring from the mine boundary, the retreating mining shall be carried out on the first mining face strip by strip with belt conveyors arranged in the upper main roadway and assistant conveying devices in the lower main roadway and inclined intake roadway; the open-off cut of the first mining face shall be built on the underside of the upper main roadway at the boundary of the mine to carry out the downward inclined mining on the strike and along the inclination.

Abstract: The disclosure discloses an automatic simulation test bench and a test method for similar materials of top-coal caving mining. Wherein, the test bench includes a test bench base, a coal seam and strata simulation module, a coal releasing simulation module, a material recovery module, automatic mixing system and a central control system. The disclosure adopts modular construction to meet the requirements of similar material simulation test of top-coal caving mining under different geological conditions and mining technology to the greatest extent. The disclosure adopts automatic control, reduces the working intensity and operation difficulty of the test personnel, and reduces the influence of human factors on the test results. The disclosure adopts a lifting structural design, so as to meet the requirements of similar simulation test of top-coal caving mining under different mining and caving ratios.

Abstract: The disclosure discloses an automatic simulation test bench and a test method for similar materials of top-coal caving mining. Wherein, the test bench includes a test bench base, a coal seam and strata simulation module, a coal releasing simulation module, a material recovery module, automatic mixing system and a central control system. The disclosure adopts modular construction to meet the requirements of similar material simulation test of top-coal caving mining under different geological conditions and mining technology to the greatest extent. The disclosure adopts automatic control, reduces the working intensity and operation difficulty of the test personnel, and reduces the influence of human factors on the test results. The disclosure adopts a lifting structural design, so as to meet the requirements of similar simulation test of top-coal caving mining under different mining and caving ratios.

Abstract: A rock mechanics test system with impact loading-confining pressure unloading and its usage method. The test system includes bearing frame unit, axial compression loading unit, impact loading unit and confining pressure loading unit. The bearing frame unit includes pedestal, column and cross beam. The column is vertically installed on both sides of the upper surface of the pedestal, and the cross beam is horizontally fixed on the upper part of the column. The axial compression loading unit is fixed at the middle position of the upper surface of the pedestal and is used to exert the axial bottom-up pressure to the sample. The impact loading unit is fixed on the cross beam and is used to exert the axial top-down impact load on the sample.

Abstract: A rock mechanics test system with impact loading-confining pressure unloading and its usage method. The test system includes bearing frame unit, axial compression loading unit, impact loading unit and confining pressure loading unit. The bearing frame unit includes pedestal, column and cross beam. The column is vertically installed on both sides of the upper surface of the pedestal, and the cross beam is horizontally fixed on the upper part of the column. The axial compression loading unit is fixed at the middle position of the upper surface of the pedestal and is used to exert the axial bottom-up pressure to the sample. The impact loading unit is fixed on the cross beam and is used to exert the axial top-down impact load on the sample.

Abstract: A reverse rotary sprinkler drilling pipe system with anti-sticking function and its application method. This system comprises the front and rear drilling pipes which are arranged in sequence, a water spraying device, a rotary device. The rear drilling pipe is connected with an external drilling rig. The front and rear drilling pipes are respectively arranged with through holes in an inner axial direction. The water spraying device comprises a first cylinder and a connecting body, and symmetrical multiple groups of water spraying holes are arranged on the inner sidewall of the first cylinder. A limit block is arranged in the upper part of the inner sidewall. The connecting body is disposed with water conveyance hole which is connected with the through hole and the inner part of the first cylinder.

Abstract: A reverse rotary sprinkler drilling pipe system with anti-sticking function and its application method. This system comprises the front and rear drilling pipes which are arranged in sequence, a water spraying device, a rotary device. The rear drilling pipe is connected with an external drilling rig. The front and rear drilling pipes are respectively arranged with through holes in an inner axial direction. The water spraying device comprises a first cylinder and a connecting body, and symmetrical multiple groups of water spraying holes are arranged on the inner sidewall of the first cylinder. A limit block is arranged in the upper part of the inner sidewall. The connecting body is disposed with water conveyance hole which is connected with the through hole and the inner part of the first cylinder.