Rockburst prevention mechanism and effect of surface fracturing for pressure relief in gob-side working faces

WANG Binchang; YAN Yaodong; JIN xin; GUO Deng; SHENG Pengfei; BAI Jianfei

doi:10.11799/ce202510006

Abstract：To thoroughly investigate the impact of surface fracturing measures on rockburst risk in gob-side working faces and its prevention mechanism,the No.20103 working face of Dahaize Coal Mine in Shaanxi was taken as an engineering case.Theoretical analysis and field detection methods were employed to study the rockburst prevention mechanism and effect of surface fracturing implemented between two adjacent working faces in reducing rockburst risk during the mining of both upper and lower working faces.The conclusions are as follows:Implementing surface fracturing between two adjacent working faces can weaken the overall mechanical properties of the rock strata before mining the upper face,thereby reducing the overall static load level below the fractured zone.During the mining of the lower face,the surrounding rock of the gob-side entry is in a relatively low static stress environment,and the surface fracturing shortens the lateral cantilever length,weakening the dynamic load energy generated by its fracture.Ultimately,this reduces the rockburst risk induced by the superposition of static and dynamic loads.Field detection results of lateral hanging roof show that,by comparing the lateral cantilever structures in the fractured and non-fractured areas,the surface fracturing effect is significant,with a notable weakening of the lateral cantilever,effectively transforming the long cantilever to a short cantilever.Surface fracturing measures play a positive role in reducing rockburst risk in gob-side working faces and can provide a reference for rockburst prevention in similar mines with gob-side working faces.