Numerical simulation of hydrous transfer within fibrouscement slates

In situ distortion of fibrous-cement slates is brought about by exposure to different temperature and hygrometric gradients across the material. The aim of this research was to understand in detail the effect of each compositional change on the physical properties, and to use this knowledge for the manufacture of slates which would exhibit improved mechanical properties. A previous paper described the experimental measurements conducted to evaluate the impact of changing the composition of the slates on the physical properties controlling hydrous transfer. In the present paper, the physical parameters obtained from the experimental work are used in a numerical model. The numerical model, NSAT, employs a finite-element method to solve the non-linear diffusion equation. The numerical model was validated and subsequent simulations are described. A theoretical model has been obtained which shows good agreement between the results from practical tests at the experimental station and the predictions of the numerical model. The results also confirm the previous hypotheses of the industrial partner. The theoretical model obtained may be used for the prediction and specification of industrial materials having improved mechanical properties, and in particular, exhibiting less distortion.[PUBLICATION ABSTRACT]