Creep features of surrounding rock and supporting time for the chamber in Jinchuan Mine No.3

In order to solve the creep control problem of surrounding rock for the crushing chamber in Jinchuan Mine No.3,the deformation of channel surrounding rock in the crushing engineering system was monitored and it showed obviously rheological properties which include rapid deformation,slow deformation and deformation stabilization.By analyzing the effect of the stress environment of surrounding rock,mineral composition and ground water on the deformation of surrounding rock,a suitable high-stress and tectonic belt rheological model was proposed and its rheological parameters were analyzed.The rheological process of Jinchuan rock is a complex process in which elastic,plastic,visco-elastic and visco-plastic deformations coexists,with a highly nonlinear characteristic.The optimum time of the second support was analyzed in theory.The second support as the best opportunity ought to be carried out within the third week after deep rock excavation and the first support in the Jinchuan Mine No.3,and the allowable deformation should be controlled between 5 mm and 150 mm.