Numerical strategies for prediction of drying cracks in heterogeneous materials: Comparison upon experimental results

Both experimental and numerical studies are presented dealing with the separation, identification and quantification of drying shrinkage incompatibilities effects between cement paste and aggregate on mechanical behaviour of cementitious materials. The experimental protocol allows us to separate these effects due to the material heterogeneity from the structural ones (drying shrinkage gradient). In order to limit the parametric study to size and volume fraction effects, a “model” (controlled) material, composed of cement paste and cylindrical sandstone aggregates, is considered. Cracking observation is undertaken using digital image correlation. These experimental investigations have been completed by a numerical study to evaluate the ability of two different models (using either smeared or discrete cracks description) to describe the experimental behaviour observed at the mesoscopic scale.