Experimental and Numerical Study of the Influence of Inclusion Size on the Drying Shrinkage Cracking in Cementitious Composites

This study investigates the effect of inclusion size on drying shrinkage cracking in cementitious materials. A series of laboratory desiccation tests on concrete with different size of inclusions are conducted. Nondestructive X-ray micro-tomography images were used to reconstruct the drying-induced shrinkage cracks of samples in desiccation tests. To better understand the mechanism of shrinkage cracking, a fully coupled hydro-mechanical bond-based Peridynamic model was developed that takes into account the interactions among deformation, cracking, and permeability evolution. The efficiency of the proposed model was verified through two benchmark problems. The influence of inclusion size on shrinkage cracks was numerically analyzed by reproducing experimental results and conducting a parametric study. The results indicate that, as the size of the inclusion increases, the quantity of drying induced cracks increases while the length of the cracks decreases and the average width of the cracks increases. However, the distribution of cracks appears to be unaffected by the size of the inclusion.