CREEP DAMAGE MECHANISM AND BACK ANALYSIS OF OPTIMUM SUPPORT TIME FOR SOFTEN ROCKMASS
软弱围岩蠕变损伤机理及合理支护时间的反演分析

Based on creep damage mechanism of the soften rockmass,it is proposed that the creep damage of rockmass is composed of deformation damage and time damage. Using the creep model of Burgers and introducing the creep damage variable,the visco-elastic deformation regularities for the round tunnel are researched by the theory of displacement back analysis. A rational method to determine supporting time is proposed for the soften rockmass tunnel. The proposed method is proved rational by practice.