Whole section anchor–grouting reinforcement technology and its application in underground roadways with loose and fractured surrounding rock

• Roadways deformation with loose and fractured surrounding rock is large and difficult to control.
• Plastic zone distributes in oval shape with different forces in horizontal and vertical direction.
• Optimization of the anchor array pitch was numerically simulated by FLAC3D.
• Whole section anchor–grouting reinforcement technology was successfully experimented.

Strata control technology for roadways with loose and fractured surrounding rock is one of the most challenging areas in underground roadway support. Based on the case of the serious deformations that occurred in a western main roadway of a Chinese coal mine, this paper analyzes the characteristics and influencing factors of deformation of roadways with loose and fractured surrounding rock. A mechanical model of the roadway’s surrounding rock has been established to study the different forces at play in the plastic zone of the roadway via means of site observation, theoretical analysis, numerical simulation and onsite experiments. Based on the double shell anchor–grouting reinforcement mechanism, whole section anchor–grouting reinforcement technology (WSAGRT) was implemented in the coal mine with the pertinent support parameters optimized by numerical simulation. The results show that the deformation of the rock surrounding the roadway has been held in check effectively, and thus WSAGRT warrants a safer and more effective mining environment.