Crackhealing of rock mass in fault zones after earthquake plays an important role for hydraulic response for the earthquake. In order to study the healing effect of fractured rock mass on the spatiotemporal evolution law of permeability in deep fault zones, we introduced creep effect of fracture to the network coupled model of discrete fractures. On this basis, a new spatiotemporal evolution model for fractured rock mass based on fluidsolid coupling was built, and the coupled equations were solved with the software of COMSOL Multiphysics. The results show that, before sealing, common coupled seepage achieves a steady state. Due to complete seepage channel, the fluidsolid interaction can’t change fluid pressure at any given time. As sealing happens, under the influence of creep, fracture aperture and permeability of unit body decrease, but fluid pressure increases. The conclusions can provide a theoretical basis for healing mechanism of rock mass and evolution analysis of permeability in fractured zones after earthquake.
Key words
fractured rock mass /
creep effect /
permeability；fracture aperture；fluidsolid coupling
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