Abstract：Using principle of statistics and FLAC3D，the three-dimensional porous structural models of sandstone are reconstructed. On the basis of the 3D porous structural models，the influences of porous structure parameters(pore number，pore radii distribution and space position distribution) on mechanical performances of sandstone are explored through a number of Brazil disk split tests with different pore distribution characters parameters by means of numerical simulation. The results indicate that porosity affects the failure states of disk models greatly. When the porosity is smaller，the tensile failure is main failure mode. When the porosity is larger，the tensile failure and shear failure act together. With the increase of porosity，the tensile strength decreases with exponential distribution. The split failure region of disk model is larger with the smaller pore radii distribution parameters. The pore radii distribution has some influences on tensile strength of disk model with smaller porosity. The influence of pore space position distribution on disk model failure mode is mainly concentrated in the place of crack occurring. It does not change failure mode and crack number of disk model. The effect of pore space position on tensile strength of disk model can be ignored. The achieved results disclose the intrinsic mechanisms of deformation and failure of rock and supply references for studying the influence of porous structure parameters on physical-mechanical performances.
