Mesoscale Modeling for Predicting Effective Properties and Damage Behavior of Geopolymer Concrete.

Geopolymer concrete is a sustainable construction material and is considered as a promising alternative to traditional Portland cement concrete. However, there is still not much research on the effective properties and damage behavior of geopolymer concrete with consideration of its heterogeneous characteristics by means of mesoscale models combined with the regularized microplane damage model. Here, in this research, an easy and simpler approach for generating concrete mesoscale models and characterizing the angular characteristics of aggregate particles is presented. After the proposed mesoscale modeling was validated by numerical, experimental and theoretical models, it was employed further to predict the effective properties and damage behavior of geopolymer concrete. The obtained results show that the effective elastic modulus and compressive strength of geopolymer concrete were greatly affected by the volume fractions of aggregate, while no significant influence on Poisson's ratio was found. The evolution of damage and coalescence of cracks were affected by the volume fractions and spatial distribution of aggregate particles, which resulted in the different failure patterns in the mesoscale model of geopolymer concrete manufactured by different volume ratios of aggregate.