2D Model of Capillary Transport of Water in Aerated Concrete

Abstract

Saturation degree of aerated concrete strongly affects not only all its thermal-technica properties, but regarding to the risk of freezing, also the strength properties. The aim of this paper is to discuss existing approaches to model capillary water liquid transport in aerated concrete and description of the new, simplified 2D computer mathematical-physical model for the solution of this transient phenomenon. The new model is based on using specific water content gradient as a potential for liquid water movement and has been compared with current established software WUFI and validated with laboratory experiments carried out. The experiments also demonstrate the significant influence of hydrostatic pressure on increasing the saturation speed of the material by liquid water. In the conclusion we discuss the limits of this new model and its further possibilities which allow for solving the effect of hydrostatic pressure on water saturation.Saturation degree of aerated concrete strongly affects not only all its thermal-technica properties, but regarding to the risk of freezing, also the strength properties. The aim of this paper is to discuss existing approaches to model capillary water liquid transport in aerated concrete and description of the new, simplified 2D computer mathematical-physical model for the solution of this transient phenomenon. The new model is based on using specific water content gradient as a potential for liquid water movement and has been compared with current established software WUFI and validated with laboratory experiments carried out. The experiments also demonstrate the significant influence of hydrostatic pressure on increasing the saturation speed of the material by liquid water. In the conclusion we discuss the limits of this new model and its further possibilities which allow for solving the effect of hydrostatic pressure on water saturation.