For the modeling of compression of concrete cube test blocks, I set up a macro model of concrete (assuming that concrete is homogeneous material), and a meso model of concrete (including coarse aggregate, mortar and ITZ), respectively, and carried out attribute assignment, mesh division and unit type setting. First of all, the macro model is subjected to pressure. When some node stresses of the macro model reach a self-set threshold, the unit of the macro model is replaced with the unit of the meso model in the corresponding position. How to set this?
