Prediction of movement, reaction and accumulation of multi-component medium in porous building material

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Regarding global environmental, energy and resource problems, longer life and durability of building materials and elements are strongly required in the field of architecture. Since most of the building materials are porous, the prediction and evaluation of movement and accumulation of the moisture and other diffusing substances in porous materials with a suitable precision are very important for an improvement of their durability. The objectives of this research are, to clarify how multi-component, multi-phase media exist, transfer and react in a porous building material, to propose a simplified model, and to develop measuring apparatuses of diffusivity and potential relationships.Experiments on infiltration of acid rain (solution) and diffusion of CO2 gas into concrete sample were carried out in order to investigate the position and degree of neutralization. Based on the results, difference in neutralization rates between gas diffusion and liquid infiltration was clarified. It was al … More so shown that water permeability is significantly different depending on the vertical positions of the test sample.From a viewpoint that the moisture and mass transfer through cracks have a significant influence on neutralization, and it is also affected by the external climates, the influence that the cracks have on the results was examined analytically.A gamma-ray apparatus for man-distractive moisture content measurement was designed and produced. Based on the measured results, several issues related to measurement practice were examined and measurement errors were clarified. A new theoretical approach was proposed which describes the diffusion process of multi-components in a porous material with chemical reactions. Furthermore, a simplified -method for estimating equilibrium relationships of multi-component media was proposed and its validity was examined. In particular, porous structure of and moisture transfer process in a very thin material such as clothing was studied, and an influence that the change in potential relationships caused by salt solution has on the evaporation process. Less