Research On Pre-stressed Anchor Support Technology In Dynamic Pressure And High Geo-stress Roadway Of Zaoquan Coal Mine

Recent years, with coal mining depth increasing, ground pressure becomes larger, thenumber of high geo-stress roadways increases constantly. The kind of roadways thatinfluenced by the working surface，the deformation is more serious, the roadway support ismore difficult, and the corresponding maintain and repair rate are higher. High geo-stressgeological feature is an important factor of affecting mine safety production. Hence dynamicpressure roadway support becomes the key technical problem of roadway surrounding rockdeformation control in the condition of high geo-stress. To deal with the problems, in thispaper, using theoretical analysis, numerical simulation and in-situ measurement to analysisthe characteristics of roadway surrounding rock deformation and destruction with highgeo-stress and dynamic pressure，study the adaptability of pre-stressed anchor apply to highgeo-stress and dynamic pressure roadway, and proposed the technology scheme of highgeo-stress and dynamic pressure roadway pre-stressed bolting, optimally designed theoptimization of supporting parameters and process, and applied in the No.12208auxiliarytransport roadway and No.11201return airway of Zaoquan Coal Mine of Shenhua NingxiaCoal Group, the main results are shown as following：（1）Tectonic stress is main stress in the regional stress field of high geo-stress anddynamic pressure roadway in Zaoquan coal mine, the maximum horizontal stress reaches7.1Mpa, which is the key factor that affect dynamic roadway surrounding rock deformationand destruction;（2）Pre-stress is the key parameters of bolt support system in high geo-stress anddynamic pressure roadway, pre-stressed anchor can effectively control the surrounding rock deformation, improve the surrounding rock stress status, and enhance the bearing capacity ofsurrounding rock, make surrounding rock and bolt components work together, form a uniformbearing structure as a result, and then improve the whole support ability of supporting body;（3）According to the geological conditions of12208auxiliary transport roadway and11201tail-entry, the combined support scheme pre-stress-bolt-anchor+metal net+W steelbelt was used to support high stress dynamic roadway.The results show that high pre-stressed anchor and cable system is more effective insurrounding rock deformation control. In the affection of dynamic pressure and highgeo-stress, the system can efficiently control the surrounding rock deformation, effectivelyimprove the stress state of surrounding rock of roadways, maintain the integrity of roof andtwo side coal body. Compared to the original support, the deformation of roadway reducesabout80%, the supporting effect is very significant.