Numerical Analyses Method of Rock Stability for Underground Chamber, Considering Rock Rheologic Behavior

In this paper, the rock masses ars regarded as visco-elastic media and the rheolo-gic behaviors of rock masses are simulated by Burgers model. To take the rock rheologic behavior into account for the stability analyses of homogeneous, isotropic and continuous rock masses, a method of numerical calculation has been put forward.The computations of stability analyses for underground chambers excavated in the comparatively rigid orthoclase and relatively soft sandstone show that the influence of rock rheologic behavior on the stability of rock masses can not be neglected, especially for the soft rock masses. The method, considering rock masses as visco-elastic media, is more reasonable than as elastic media in the analyses of surrounding rock stability. The development of the plastic zones in rock masses and the variations of displacement around the excavation can be predicted more accurately by using this method. And it can provide the basis for the choose of beneficial time and supporting forms.