Effects of different shapes of aggregate on the behaviour of plain concrete beam at meso-scale

Abstract

In this study, behaviour of plain concrete beam under three-point bending is simulated at meso-scale (10^-4 -10 cm). At meso-level, concrete is assumed to consists of either a two-phase or a three-phase composite material (mortar, aggregate and/or interfacial transition zone-ITZ). First, the aggregates are generated based on a given aggregates gradation and then those are placed randomly within the concrete sample following uniform distribution. The remaining space of the concrete sample is then filled with the mortar in case of a two-phase assumption. However, in three phase modelling, a part of the mortar of finite thickness surrounding the aggregates is assumed as ITZ. In this study, three different shape of aggregates: circular, elliptical and polygonal, are considered and their effect on the simulated load deformational response of plain concrete beam is studied. The simulated results are then validated with the corresponding available experimental data. A statistical analysis based on variability of aggregates generation for three different shapes of aggregates is also performed.