Predicting Early Age Temperature Evolution in Massive Structures from Non-standard Characterization Test

Abstract

Two methods are proposed to characterize the thermal fingerprint of a binder from an insulated mockup test realized on a jobsite, rather than using a classic quasi-adiabatic test in lab condition. The first part introduces the model used to compute the temperature evolution at early age, using a Finite Element solver. The second part presents the two methods. The first method is based on the estimation of the heat loss of the mockup. Then, a methodology similar to a standard quasi-adiabatic test is done, by computing (i) the total heat generated during hydration, (ii) the hydration rate and (iii) the chemical affinity. The second method is based on an imposed form of the hydration affinity function, with three parameters. A Finite Element model of the mockup is used, and a minimisation between the computed temperature evolution and the experimental one allow to identify the three parameters. The two methods are validated on a purely numerical study. Then, a real example is presented, and the relevance of the two methods are discussed.