Failure Mechanism and Control Technology of Surrounding Rock of Gob-Side Entry Retaining in Gently Inclined Coal Seam: A Case Study

In the mining regions of Southwest China, gently inclined coal seams are prevalent, leading to an increasing number of issues, such as deformation and failure of the gob-side entry retaining surrounding rock and support dumping during the production process. This article takes the 1811 working face of a specific experimental mine in the Southwest region as the engineering background, and through theoretical analysis, numerical simulation, and on-site application, it provides a comprehensive exposition of the failure mechanism and control principles of the surrounding rock in Gob-side Entry Retaining in Gently Inclined Coal Seams (GERIGICS). The research optimizes the roof cutting angle, and the flexible support technology of high pre-tightening force long anchor cable-anchor bolt-anchor net-soft film wall yield pressure (HTAAS) was proposed. The research shows that with the increase of roof cutting angle, coal seam dip angle, roadway width, and coal seam buried depth, the deformation and failure of GERIGICS surrounding rock is more significant, its shrinkage rate increases and the main roof fracture is more serious. Moreover, the (HTAAS) flexible support technology has enhanced the stability of the GERIGICS surrounding rock, reducing the shrinkage rate from 18.34 to 3.52%, thus significantly improving the control of the GERIGICS surrounding rock.