Simulation of fracture of cementitious composites with explicit modeling of microstructural features

Fracture of cementitious composites is analyzed numerically using the cohes ive surface methodology. The presence of aggregates in the cement matrix is explicitly accounted for. The composite is modeled in two dimensions as a three-phase material, the third phase being the weak interfacial transition zone in between aggregates and cement matrix. The bulk material is regarde d as elastic and fracture is described with cohesive surfaces. The cohesive surface constitutive model is motivated by experimental observations regar ding the loading-rate sensitivity of cementitious composites and analytical studies regarding fracture of planar microcracks. The model predicts the i mportant toughening mechanism of crack face bridging occurring in cementiti ous composites. (C) 2001 Published by Elsevier Science Ltd.