LBM Numerical Simulation Study On Seepage Characteristics Of Fractured Rock Mass

Fractured becomes water inrush channel,which is an important reason for water inrush in underground space engineering excavation.Therefore,the research on the seepage characteristics of fractured rock mass is of great significance in underground space engineering.LBM not only considers the motion of fluid molecules from a microscopic perspective,but also describes the statistics of fluid molecules from a macroscopic perspective.It is a new method for fluid modeling and simulation.In this paper,based on the LBM,the Poiseuille flow plate model was verified by MATLAB program simulation,then the rough fracture surface and curved smooth fracture surface were generated,and the effects of fracture width,pressure difference,roughness coefficient and curvature on the seepage characteristics of fractured rock were studied,and the research results are as follows:(1)The fluid flow velocity at the rough fracture surface is smaller than that of the Poiseuille flow theory solution,and decreases with the fracture width,which also reflects that the fluid percolation cubic law is applicable to the idealized flat plate fracture percolation.(2)As the pressure difference between the two ends of the fissure increases,the maximum value of fluid flow velocity in the fissure increases;as the value of the fissure roughness coefficient JRC increases,the slope of the seepage flow curve of each rough fissure surface increases,and the consumption of seepage flow in the fissure rock also increases,the greater the Attrition ratio of flow at both ends of the rough fissure surface.(3)With constant fracture width and other influencing factors,the seepage in the fractured rock is proportional to the-4.371 rd power of the curvature T as the curvature of the fracture surface increases,using only the curvature T as the independent variable.(4)With constant fracture width and other influencing factors,the seepage flow in the fractured rock is inversely proportional to the 1.087 th power of the relative roughness ?/b as the fracture surface roughness increases.