Grouting Seepage Model of Adjacent Gangue in Caving Zone
In order to improve the prediction accuracy of grouting diffusion range of gangue adjacent to caving zone,based on the theory of seepage mechanics,considering the influence of slurry properties,gap structure of caving zone and seepage effect,a grouting seepage model adjacent to caving zone is constructed,and the three-dimensional unsteady diffusion law of slurry seepage is analyzed.The function of slurry yield stress changing with seepage distance is introduced,and the calculation formulas of slurry diffusion range,stacking height and grouting amount are derived,and verified by numerical simulation.The results show that the grouting seepage presents the evolution law of low pressure diffusion-longitudinal penetration-lateral ex-pansion,and its shape changes from ellipsoid and cylinder to truncated cone.The diffusion mechanism of adjacent grouting is revealed,and the start and stop of grouting diffusion in caving zone are controlled by yield stress.When the yield stress of slurry is less than shear stress,the slurry begins to spread.The porosity of caving zone decreases,the tortuosity of seepage path increa-ses,the seepage resistance increases and the diffusion distance of slurry decreases.The research results can provide theoretical reference for efficient grouting of adjacent gangue in caving zone.
adjacent gangue groutingseepage and diffusionmine solid wastetheoretical model