Déformations endogènes de pâtes de ciment au très jeune âge: Analyse critique et développement métrologique

ABSTRACT The objective of this paper is to analyse and to compare the results obtained with three different experimental methods used for the measurement of autogenous strain of hydrating cement pastes. Two (horizontal and vertical) linear measurement systems and a rotary volumetric device, especially designed for the study of very early-age strain, have been developed. The tests have been performed on Portland cement pastes with three different water-to-cement ratios (W/C) equal to 0.25, 0.30 and 0.40. The effects of bleeding on both the linear and the volumetric results and of the immersion liquid absorption on the volumetric results have been quantified. The critical analysis of these results yields the conclusion that, among the three test methods used and in the range of W/C ratios investigated, the dynamic volumetric method is the most adapted for the measurement of very early-age autogenous strain even if some improvements have to be made in the choice of the immersion liquid.