A joint model based on particle flow was built successfully and the mechanical properties of the fill joint were investigated in this study. The morphology of damage and the crack evolution mechanism of roughness of the jointed model were also analysed from the viewpoint of meso-mechanics.At the same time,the influence of the value of the JRC( joint roughness coefficient),fill strength,interface,and fill thickness on the mechanical behaviour have been analysed. The detailed results are as follows:( 1) The n...