Application of the maturity concept for the prediction of restrained autogenous shrinkage of cement pastes

This research work concerns the study of the autogenous restrained deformations of cement pastes at an early stage in controlled-temperature conditions. Portland cement and slag cement pastes prepared with a water-to-cement ratio W/C equal to 0.3, are investigated at 15, 20, 30 and 40°C. The measurement method for restrained shrinkage is the ring test. The experimental device is equipped with a peripheral water circulation system to keep the specimen in quasi-isothermal conditions. The results show that the curing temperature significantly influences the age of the first through crack and the ring strain at cracking. The capacity of the traditional maturity concept to quantify the thermal effect on the age of cracking has then been assessed by calculating apparent activation energies from Vicat setting times and from cracking ages measured with the ring test