Abstract:
Some strain-type rock bursts, mainly stratified flaking and splitting destruction forms, occurred in the diversion tunnel construction of a hydropower station in Xinjiang during excavation, threatening the safety of equipment and personnel. Aiming at the defect that the present standards could not give depth of burst pit and could not provide accurate judgment for non-circle tunnels, we apply the brittle rock mass failure forecast criterion based on regional ground stress regression analysis. By the feasibility analysis of the presented method, the new method and standard method are used to determine the rock burst possibility of the remaining section of diversion tunnel. The results show that the brittle rock mass failure prediction criterion is suitable for forecasting the depth of burst pit, the remaining sections are flaking and splitting burst with the possibility of middle rock burst and even strong rock burst in local positions. The results can be used in the excavation and support design of the remaining section. This new method could provide a reference to judging the rock burst possibility of deep hard rock mass.