The influence of Li2CO3 on the kinetics of the concrete hardening at the temperature of 80°C

Abstract

Abstract. The present work was done during the research carried out by the authors, the aim of which was to develop methods for reducing energy costs in the manufacture of precast concrete and reinforced concrete structures for civil engineering. The paper presents the results of the analysis of the addition of lithium carbonate (Li2CO3) effect on the rate of hydration of Portland cement and the concrete obtained on its basis under high temperature conditions (80°C). The heat release curves were obtained during the hydration of samples based on a cement binder using the isothermal calorimetry method. The addition of Li2CO3 was taken in dosages from 0.5% to 2.0% by weight of cement. The graphical dependences of the heat release of the exothermic hydration reaction from the used dosage of lithium carbonate in the first 10 hours of hardening are established and presented in the paper. The obtained heat release data were compared with the graphs of the hardening of the samples tested by the standard method.