Effect of temperature on the development of C-S-H during early hydration of C3S

International audienceIt is known that accelerating or retarding hydration of OPC by temperature has consequences on the final properties of concrete, the lower the temperature the higher the final compressive strength. It seems that this effect is related to the properties of the hydration layer formed at early age. Early hydration of C3S has then been studied at temperature ranging from 5 to 45°C in isothermal conditions. The percentage of hydration is estimated from calorimetric measurements and the surface developed by the growth of C-S-H is estimated from Nuclear Magnetic Relaxation Dispersion method. Both data are numerically simulated according to a C-S-H growth model described previously. The good agreement between the experimental and numerical data validates the C-S-H growth model on the tricalcium silicate surface. The higher the temperature, the denser the C-S-H layer is