The differences in deformation characteristics between rigid and flexible components are fundamental factors that affect the overall properties of semi-flexible pavement material.On the basis of digital image processing technology and finite element analysis method,the internal weak parts of semi-flexible material were analyzed.Results indicate that the shrinkage deformation of cement mortar is the main factor that influences the internal stress of the semi-flexible material.The larger the porosity of asphalt mixture is,the more the number of stress concentrations appear.This study determined the deformation control index of cement mortar to provide a theoretical basis for the rational design of semi-flexible material.