Collaborative prevention and control technology of"fracture-injection-discharge-support"for thick and hard roof working face crossing faults

XU Dong; ZHENG Rui; LI Yinglong

doi:10.11799/ce202506004

Abstract：In view of the difficulty in surrounding rock stability control and frequent disasters during the mining of thick and hard overburden roof working face crossing faults.We adopted theoretical analysis,numerical simulation,and field test to study the characteristics of overlying rock migration and the dynamic evolution law of surrounding rock stress during the working face crossing faults.A collaborative prevention and control technology of"fracture-injection-discharge-support"was proposed for the working face crossing faults.Research results show that as the size of coal mass between the working face and the fault plane decreases,the risk of instability caused by the sliding of thick and hard roof along the fault plane increases.There is a stress barrier effect on the fault plane,with an increased stress zone in the hanging wall area and a decreased stress zone in the foot wall area.The working face crossing fault is divided into five periods,fault stationary period,fault activation period,fault movement period,fault stress release period,and fault stability period.Before the fault movement period,the coordinated measures of rock stress-relief and solidification are adopted in stages,which can improve the stress distribution environment and the structure of the surrounding rock in the stope,reduce the periodic weighting intensity by 35.8%～57.6%,bring down the impact dynamic load of the working face,and maintain the roadway deformation of within the range of 388～589 mm.The stability of the surrounding rock in the fault area was significantly improved,achieving safe and smooth passage of the thick and hard overlying rock roof working face through the fault.