Abstract In order to research the influence of karst cave ahead of roadway on surrounding rock stability, a numeri? cal model is established by FLAC3D considering the interaction of seepage, stress and damage,the variation charac?teristics of stress, deformation, plastic zone and seepage field of surrounding rocks during excavation are analyzed.The numerical results show that：(1) when working face is close to krast cave, the karst cave has certain effect of inhibition to the zonal disintegration of surrounding rock ahead of roadway; (2) with the decrease of distance from karst cave, the maximum displacement of rock mass will gradually increase and present "abrupt change" characteristics,while the position of maximum displacement will change with the variation of water inflow channel; (3) when waterproof pillar is less than a certain thickness, the water inflow of surrounding rocks will suddenly increase and show obvious water burst; (4) seepageand variation of permeability coefficient of surrounding rocks are the basic reasons to cause collapse, chip off-falling and water inflow.
Abstract：
In order to research the influence of karst cave ahead of roadway on surrounding rock stability, a numeri? cal model is established by FLAC3D considering the interaction of seepage, stress and damage,the variation charac?teristics of stress, deformation, plastic zone and seepage field of surrounding rocks during excavation are analyzed.The numerical results show that：(1) when working face is close to krast cave, the karst cave has certain effect of inhibition to the zonal disintegration of surrounding rock ahead of roadway; (2) with the decrease of distance from karst cave, the maximum displacement of rock mass will gradually increase and present "abrupt change" characteristics,while the position of maximum displacement will change with the variation of water inflow channel; (3) when waterproof pillar is less than a certain thickness, the water inflow of surrounding rocks will suddenly increase and show obvious water burst; (4) seepageand variation of permeability coefficient of surrounding rocks are the basic reasons to cause collapse, chip off-falling and water inflow.
2020, Vol. 57 