Damage and failure mechanism of anchored surrounding rock with impact loading

In order to study the damage and failure characteristics of anchored surrounding rock in rock burst roadway, the dynamic response characteristic of anchored surrounding rock under impact loading was analyzed. The damage of surrounding rock and anchorage interface were tested and the mechanical properties of the bolt before and after the im- pact load were compared through the site tests. The results show that the anchorage performance reduction and failure were induced by repeated tension and extrusion under impact stress wave. After impact loading,the strength and integ- rity of roadway surrounding rock decreased sharply with a mount of internal fractures’development,then,the anchored performance of bolt system became invalid eventually. The performance of bolt supporting material was reduced,and the reduction of rod elongation reached 13. 8% ,tensile strength decreased 6. 6% ,impact absorbing energy decreased 24. 3% ,plastic deformation and grain distortion occurred,and micro metallographic organization disordered. The com- prehensive supporting method,including anchor grouting,full-size grouted,bolt and anchor combined support with high strength,high elongation,and high impact toughness,can ensure the surrounding rock stability under impact loading.