Abstract：Pentamode materials are new artificial metamaterials called as PM materials. Although PM materials belong to elastic materials, they possess only one load-carrying mode under static forces, and can transmit only one kind of elastic waves under dynamic excitation because of their special micro-structures. In the paper, two kinds of micro-structures of PM materials with different elastic properties are constructed, and one of them can transmit elastic expansion waves while the other transmit elastic shear waves. Then the effective elastic modului of the micro-structures are calculated and analyzed by employing the representative volume element method and the homogenization method, respectively. The results show: (1) The reasonable procedure for analyzing PM materials should be divided into two steps. The first step is to employ the truss model of micro-structures to calculate the effective elastic modului of PM materials and to judge whether the effective elastic modului satisfy the definition of PM materials; the second step is to adopt the solid model to analyze the relationship between the structural parameters of micro-structures and the effective elastic modului and to finish the material design. (2) The representative volume element method is suitable for analyzing the effective elastic modului of PM materials.
2015, Vol. 36 
