Numerical Simulation Of Compression Failure And Fluid Solid Coupling Considering The Heterogeneity Of Granite

In natural conditions,some rocks(such as granite)are composed of different components,and the physical and mechanical properties of the components are quite different.Therefore,it is difficult to regard them as homogeneous bodies in the study of rock mechanics.Engineering excavation will cause changes in the stress field,and the inevitable impact of groundwater,which is a great challenge to the stability of rock in engineering.How to grasp the deformation mechanism and failure mechanism of real rock in complex environment by various means has become a very important problem in the field of rock mechanics.In view of this,aiming at the heterogeneity of granite and the fluid solid coupling in engineering,the numerical simulation of fluid solid coupling and failure process considering granite heterogeneity is carried out.The main research contents and achievements are as follows:(1)Through ABAQUS granite homogeneous calculation model is established,numerical simulation of single axis,three axis and three axis compression condition of fluid solid coupling on the granite rock mechanics is considered as homogeneous response and deformation,given the rock failure shape,stress distribution,the whole process of stress-strain curve and the seepage velocity vector diagram.It is concluded that the failure mode of the homogeneous calculation model is relatively simple.Confining pressure can effectively increase the loading capacity of rock specimen,and the seepage pressure will change the grid stress and strain state of the rock sample,resulting in changes in the form of failure.(2)The establishment of the heterogeneous model,change the component strength and spatial distribution carry on three axial compression simulation,obtained weak components on the rock failure induced by rock structure,often along the weak components of weak surface forming macro failure surface.The heterogeneous granite based on real section calculation model of single axis and three axis compression simulation,the influence factors for the failure of granite is the most important form of heterogeneity and not stress state,therefore in the study of rock mechanics can not be neglected the heterogeneity.(3)The heterogeneous calculation models for different confining pressure and osmotic pressure under three axial compression fluid solid coupling simulation that,when the confining pressure is low osmotic pressure will change the rock failure form,effect of osmotic pressure on the peak stress decreases with the increase of confining pressure.The granite is dense and hard rock,and the permeability is very low without plastic deformation.As the plastic strain is produced,the water will flow along the plastic transfixion zone and form the seepage path.