Elasto-plastic analysis of block structures through a homogenization method

The paper describes the development and numerical implementation of a constitutive relationship for modeling the elasto-plastic behavior of block structures with periodic texture regarded at a macroscopic scale as homogenized anisotropic media. The macroscopic model is shown to retain memory of the mechanical characteristics of the joints and of the shape of the blocks. The overall display anisotropy and singularities in the yield surface arising from the discrete nature of the block structure and the geometrical arrangement of the units. The model is formulated in the framework of multi-surface plasticity. It is implemented in an finite element (FE) code by means of two different algorithms an implicit return mapping scheme and a minimization algorithm directly derived from the Haar-Karman principle. The model is validated against analytical and experimental results the comparison between the homogenized continuum and the original block assemble shows a good agreement in terms of ultimate inelastic behavior, when the size of the block is small as compared with that of the whole assembly