Effect of aggregate particle size on mortar pore structure

The purpose of this work is to evaluate the effect of aggregate particle size on the pore size distribution (PSD) of mortars. the aggregate particle size was characterized by the surface-to-volume ratio (SVR), experimental preparation of 4 particle size range of single gradation mortar, and their coupling to form a synthetic gradation was used as a comparison. This assessment allows the establishment of a close relationship between aggregate’ SVR and mortar parameters such as porosity, fractal dimension of PSD, double T2 cutoff and permeability. Pores were divided based on double T2 cutoff to evaluate pore connectivity, and magnetic resonance imaging (MRI) visualized the distribution of pore structures. The main results show that aggregate’ SVR is the main parameter affecting the most probable pore size and pore connectivity of the mortar, with the decrease of the SVR, the pore structure becomes rich, especially mesopores and macropores increase significantly.