Comparative analysis of phenolphthalein indicator, XRDA and FTIR methods for measurement of carbonation depth of concrete

Abstract

Carbonation in concrete demands prime concern as it is a major deteriorating factor in concrete structures in our surroundings. The accurate determination of impact of carbonation in concrete is still a challenge. The naturally occurring carbonation process in our environment is extremely slow. Hence in order to analyze the effect of carbonation in concrete in concise duration, an accelerated carbonation chamber is required to increase the rate of carbonation under given parameters for experimental purpose. Phenolphthalein indicator methods by far the most conventional method of determination of depth of carbonation in concrete, being most economic and quick. However, it does not provide accurate results with respect to carbonation depth. This paper presents an experimental study of carbonation effect of concrete by advanced methods such as XRDA and FTIR methods. The process of carbonation has been carried out in an accelerated carbonation chamber under controlled environmental conditions using ordinary Portland cement (OPC) concrete at Water/cement (W/C) ratio 0.4, 0.45 and 0.5. Study shows that carbonation depth obtained from advanced methods is greater than that obtained from conventional method and that the carbonation depth increases with the increase of W/C. © IAEME Publication.