Taking 3302 return air lane retention as the engineering background,this paper analyzes the technical scheme and application effect of cutting top and unloading pressure retention.In the retaining lane of 3302 return air lane,the advance support is carried out by high-strength anchor cable to create good conditions for the subsequent retaining lane.Through directional presplitting blasting,the roof of the roadway section and the goaf roof form the top cutting line,and the goaf roof collapses along the top cutting line.Temporary roof support and stoppage support can ensure the stability of roof and avoid the intrusion of broken gangue in gob during gob caving.After the engineering application,the roof subsidence of the remaining section of 3302 return air lane is controlled within 251 mm,and the road-way section can meet the needs of subsequent use.
mining roadwaytop cutting pressure reliefkeep the lane along the hollow