Influence of agricultural residue ash on early cement hydration and chemical admixtures adsorption

摘要

This study investigated impacts of internal surface area of wheat straw ash (WSA) and rice straw ash (RSA) on cement early hydration as well as on chemical admixture adsorption in cementitious systems. Results were compared to those of silica fume. Hydration kinetics and mortar strength experiments showed RSA and WSA to have similar reactivity to silica fume. High surface areas of WSA and RSA did not increase early hydration as compared to silica fume. However, high surface areas of WSA and RSA dramatically increased their adsorption capacity of air entraining agents and retarders compared to silica fume. (C) 2015 Elsevier Ltd. All rights reserved.