ABSTRACT
Abstract A lot of literature deals with the influence of the type of cement and mineral admixtures on the freeze-thaw resistance of concrete. However, the analyses are contradictory. The aim of the present work is to classify the influence of cement characteristics on the behavior or mortars subjected to a thermo-mechanical loading. Two parameters are investigated : the chemical analysis and the specific surface area of cement and the type of pozzolan (silica fume or metakaolin). The mortars are cast with a cement: sand ratio of 3.375 and present the same workability. The damage of prismatic samples (40 x 40 x 160 mm3) subjected both to three-point flexure and freeze-thaw cycles is evaluated. The rate of loading is 20 % of the 28-day tensile strength. A durability factor is therefore defined, allowing the rating of the different parameters. The best results are obtained with a cement presenting those characteristics : low specific surface area, low C3A content and high €28 amount. Pozzolanic admixtures and low water to cement ratios increase the durability of mortars subjected to flexural loading. The investigation of microstructure is interesting to understand the evolution of their mechanical properties.
