Study of overlying strata creep affected by seepage in backfilling mining process

Because the creep properties of overlying strata will be affected by the groundwater seepage in the backfilling mining process, which will finally affect the long-term stability of the overlying rock and surface. Starting from the general solution of the rheological mechanics, this paper has derived the stress equilibrium equation of the rock under the action of stress and water pressure according to the equation of hydrostatic equilibrium, the principle of effective stress, and the geometric equations based on the Burgers model in the classic rheology. Meanwhile seepage field control equation has been acquired according to the Darcy's law and the seepage field equation of continuity. Finally the seepage-creep coupling mathematical model has been founded. Besides, based on the actual geologic conditions of some mine, the paper has also systematically studied the overlying strata creep rules under different mining methods and different pore water pressures according to the derived mathematical model of seepage-creep coupling and on the computing platform of Comsol Multiphysics. ©, YYYY, China University of Mining and Technology. All right reserved.