Indentation of interlocked assemblies: 3D discrete simulations and experiments

The auto locking structures are a new category of hybrid materials. They consist of periodic pavings of elementary blocks. The geometry of the blocks, the friction between the blocks as well as the boundary conditions applied to the edge of the assembly play a central role in the cohesion of the assembly. The effect of the boundary conditions has been experimentally quantified by performing indentation tests on structures built with cubic blocks made of alumina. The effect of the other design parameters is studied using two numerical methods. For the first method, a numerical tool that can simulate the behavior of interlocked structures built with cubes or osteomorphic blocks has been developed. This code uses the discrete element method. For the second method, the finite element commercial software Abaqus has been used to complete the results of the discrete element code. Then, the study of discrete element simulation brought to light the existence of a master curve that is similar to the experimental indentation curves. Therefore the indentation curves can be described by few parameters. The evolution of those parameters can be studied according to the design parameters.