Modelling shrinkage of concrete from moisture lost using moisture diffusion theory

Abstract

This paper proposes a model to predict the shrinkage of concrete based on the moisture lost from the concrete in the process of drying. The drying of concrete causes the decrease in relative humidity within concrete, which is usually considered responsible for the shrinkage of concrete. The fall in relative humidity was correlated to the moisture lost according to diffusion theory. Incorporating existing relative humidity–shrinkage relationships, the shrinkage of concrete was then modelled as a function of the moisture lost. The predicted shrinkage was compared with the experimentally measured results and good agreement was achieved. The paper also illustrates that the model can represent non-uniform shrinkage and the effect of specimen size on shrinkage. However, further development of the model is required to accommodate the influence of aggregate and changes in environmental conditions.