Publication dans des actes
Résumé : Bulk hydrophobic treatments of cement-based materials have an excellent industrial application potential. According to the design process of the hydrophobic cement-based material, the hydrophobic agent can be incorporated as admixture, neat emulsion or powder. In this study, a non-ionic water based emulsion of silane monomer and silane resin is used as “integral water repellent” treatment of mortar. The setting and early age hardening of mortars with water/cement ratio of 0.5 and two types of cement (CEMI and CEMIII) were assessed by means of isothermal calorimetry, penetration resistance tests and ultrasonic transmission measurements. The use of ultrasonic measurements allows the continuous monitoring of the evolution of the p- and s- wave velocity through mortars and consequently, a whole picture of the early age elastic properties development of mortars. A decrease in the Young’s elastic modulus amplitude evolution was noticed when the silane emulsion is used. Furthermore, with the addition of water repellent, the penetration resistance tests have also shown that the setting time is retarded. These results are correlated with the data obtained with the ultrasound device as well as those of the isothermal calorimetry campaign.