Heat of hydration models of cementitious materials

Silica fume from certain metallurgical operations, granulated slag from metal industries and fly ash from the combustion of coal are industrial by-products that have been widely used as mineral admixtures in normal- and high-strength concrete. Due to the reaction between calcium hydroxide (CH) and mineral admixtures, the hydration of concrete containing mineral admixtures is much more complex compared with that of Portland cement. In this paper, the production of CH in cement hydration and its consumption due to the reaction of mineral admixtures is considered in order to develop a numerical model that simulates the hydration of concrete containing silica fume, fly ash or slag. The heat evolution rates of these admixture-blended concrete were determined by the contribution of both cement hydration and the reaction of the mineral admixtures. The proposed model was verified with experimental data on concrete with different water/cement ratios and mineral admixture substitution ratios.