A binary-medium-based constitutive model for geological materials based on the statistical meso-breakage concept and mean-field homogenization

Abstract

This paper is devoted to determining the inelastic responses of geological materials by the binary-medium-based constitutive model. The geomaterials are conceptualized as two-phase composites that are composed of the bonded medium of elastic–brittle nature and the frictional medium of elastoplastic nature. The evolution of meso-structure upon loading is considered by the progressive transformation of the bonded medium into the frictional medium. By introducing the statistical meso-breakage concept, the breakage ratio indicating the degree of such transformation is determined by statistical approaches. The interactions among inclusions (the bonded medium) and matrix (the frictional medium) and the influence of the varying breakage ratio are considered with the help of the double-inclusion model within the framework of the mean-field homogenization scheme. An application is presented for the structured/bonding geomaterials based on the proposed model. The comparisons between computed results and experimental data of three kinds of structured soils show that the proposed model can reproduce the typical behaviors of cemented/structured geomaterials.