Measurement of early-age temperature rises in concrete made with blended cements

Abstract

The advisability of controlling the temperature rise and fall in concrete at early age is well recognised as one of the factors preserving long-term performance and durability of structures. Of particular importance in design of water-retaining and massive concrete structures is T1, the difference between peak temperature of the section and mean ambient temperature. In previous studies, a cement hydration model was developed in order to predict T1 for concrete made with low heat (LH) and very low heat (VLH) special cements. To test this model, a study was carried out to measure the early-age temperature rises for concrete elements containing blended cements, meeting the requirements for the LH and VLH classes. The effects of cement heat class, cement content, formwork type and section thickness on the temperature rise were evaluated for both cement types. Verification of the established models was evaluated by comparing measured temperature rises with those predicted. It was found that the model proposed in previous studies gave satisfactory prediction of T1 values.