Effect Of Water/Cement Ratio And Curing Temperature On Early-Age Shrinkage And Self-Induced Stresses Of High Performance Concrete

This paper presents the results of an experimental study dealing with the influence of water/cement (w/c) ratio and curing temperature on the autogenous deformations and self-induced stresses in early-age concrete. Two concrete mixes, w/c ratio 0.33 and 0.37, were cured isothermally at 10, 20, 30 and 40°C. The linear deformations of a free specimen and the self-induced stresses of a fully restrained one were measured in the first six days after casting. The lower w/c ratio mixture experienced both higher deformations and higher self-induced stresses. Higher temperatures, on the contrary, did not always lead to higher deformations in the observed period, but generally caused a faster shrinkage and a faster development of self-induced stresses. Numerical simulation of hydration at different temperatures allowed identifying in the different porosity of the pastes one of the causes of the unsystematic dependency of autogenous deformation on curing temperature.