Roadway supporting design based on surrounding rock deformation and failure mechanism
Due to the impact of close range coal seam mining,the deformation of the roof and surrounding rock on both sides during ad-jacent coal seam excavation is severe.Taking the No.21320 working face of Xiayukou Coal Mine in Hancheng Mining area as the back-ground,through theoretical analysis,numerical simulation,and on-site measurement,the fracture characteristics of the roof,floor,and two sides of the close range coal seam fully-mechanized mining face were studied.The research results indicated that the vertical stress at a depth of 13 meters on the compacted foor of the overlying goaf was about 14.1 MPa,and the horizontal stress was about 14.2 MPa.The maximum depth of damage to the floor at the edge of the goaf was 39.8 meters,the maximum failure length of the floor of the goaf along the horizontal plane direction was 102.27 m;the stress concentration of the coal pillar increased under the influence of the goaf of the upper protective layer and the excavation of No.21320 intake airway,the failure depth of the floor in the goaf was about 5-7 m;After the excavation of the intake airway of No.21320 working face,most of the 10 meter coal pillar left between the goaf of No.21320 work-ing face was penetrated by the plastic zone.Based on this,the original plan was optimized.Through on-site experiments,it was found that the roof,floor,and two sides had a displacement of less than 200 mm,and most of the time,the displacement of the two sides was less than 100 mm.This indicates that after enlarging the spacing of the anchor rod and cable supporting in the No.21320 intake airway,it will not have a significant impact on the roadway and can shorten the supporting time and increase the monthly footage of the road-way.
close range coal seamdeformation and failure of surrounding rockroadway supporting design
万方数据
维普
