An atomistic based continuum level 3D mode-I meso-fracture criterion for cement-based concrete

Abstract

This paper establishes an atomistic based continuum level 3D mode-I meso-fracture criterion for cement-based concrete from a multiscale perspective. Firstly, on the basis of the 3D self-consistent finite stress model and the 3D mesoscale crack path model, a meso-fracture criterion is theoretically deduced by considering both the crack tip stress state and the crack path energy consumption conditions. Secondly, with the help of MD simulation technique, a systematic atomistic level modelling approach for the study of interaction behaviors between mortar and aggregate in cement-based concrete is developed, and based on which, a new determination method for the critical mesoscopic fracture index is proposed. Thirdly, using mesoscale fracture test results as experimental benchmark for numerical models, the proposed meso-fracture criterion is verified through FE simulations based on a tri-phase numerical model. It is expected this work could lay a foundation for the following investigations on concrete performance design.