Investigation of resistance to ageing by SO2 on some building stone

Abstract

Building stone has widespread use in construction materials because of its special characteristics that are related to high performance as a resistance building materials and color properties. Despite the widespread use of building stones, it is susceptible to alteration by some pollutants such as sulfur dioxide, nitrogen oxide, carbon monoxide concentrations in the air become more serious damage in building stone. The objective of the present work was to demonstrate how resistance to ageing by SO2 action in the presence of humidity influence the surface micro-roughness, gloss and color of six distinct stone varieties belonging to marbles, travertine, and granite. For this purpose, the samples were subjected to an experimental process under two different SO2 concentration using an EN 13919 standard. The surface roughness, gloss and color of the samples were measured at the process in the concentration of A% to B%. And also, surface topographies of the natural stone samples were characterized by using scanning electron microscope (SEM). The results are discussed in relation to the SO2 reaction, forms of gypsum and the surface topography of the samples. Mainly due to the the solution concentrate increasing, different levels changed of roughness, gloss and color values were observed for the all of natural stones. SEM images of the studied stones indicated that after acid-calcite interaction, gypsum was formed rhomboidal-shaped, long prismatic and small rosettes.