Effect of Moisture in Concrete on Fluid Absorption

Abstract

One of the most important parameters affecting unsaturated flow in ordinary concrete is the degree of water saturation of the pore system. The available pore volume for fluid transport is reduced by the moisture content inside the pores. This investigation showed that, if no chemical reactions occur, the reduction of the absorption rate of fluids in concrete specimens with increasing degree of water saturation is the same function of the water saturation independent of the fluid type. The penetration depth of the fluids in concrete was determined by thermal imaging after splitting the concrete specimens. This method allows the fluid distribution inside the specimens to be visualized. A prediction model for fluid transport, based on the concrete composition and on the physical parameters of the fluids, is presented. A good agreement is observed when values obtained from the prediction model are compared to the experimental results in defining the effective pore size range in concrete which influences the transport of fluids.