Experimentally validated meso-scale fracture modelling of mortar using output from micromechanical models

Abstract

This paper presents a validation process of the developed multi-scale modelling scheme on mortar composites. Special attention was paid to make the material structure of real and virtual mortar specimens comparable at the meso-scale. The input mechanical parameters of cement paste (both bulk cement paste and interfacial transition zone) at the meso-scale were derived from results of micromechanical modelling through a volume averaging approach. Two constitutive relations for local elements were assumed and tested. By comparing with the experiments, the model using linear-elastic constitutive relation showed to be capable to reproduce the experimental load-displacement response satisfactorily in terms of the elastic stage and peak load. However, in the non-elastic stage a more realistic load-displacement curve can be simulated by considering the softening of cement paste using a step-wise approach. More importantly, the proposed multi-scale modelling scheme is validated by the experimental measurements. The proposed development offers the opportunity for the meso-scale model to become fully predictive.