Computer simulation of the microstructure of ITZ and its basic charactristics

In view of the importance of the interfacial transition zone (ITZ) in the vicinity of an aggregate to the physical and mechanical properties of concrete, it is necessary to determine its statistical characteristics and width. Once the cement area density at any point in the ITZ and its width are known, some other physical and mechanical properties of the concrete can be determined based on the theory of micro-mechanics. The intention of the present paper is to numerically simulate the distribution of cement particles between aggregates, taking into account the effect of the aggregate interface. Based on the simulated distributions of cement particles, the basic characteristics of ITZ are studied. Simulated results show that the average cement area density at any point from the aggregate interface converges asymptotically to a fixed value when the number of simulations tends to infinity and that the width of ITZ is about 50 mu m, which coincides with the experimental results reported in the research literature.