120-127The relationship between the late-age hydration and strength development of cement-slag mortars have been investigated by measuring the compressive strengths and the non-evaporable water contents. The results show that the late-age strength increases with increasing the slag content. Increasing the fineness of slag makes greater contribution to the late-age strength improvement at high water to binder ratio than that at low water to binder ratio. At lower water to binder ratio, the increasing rates of compressive strength and non-evaporable water content are smaller. There is a linear relationship between the increasing rate of compressive strength and the increasing rate of non-evaporable water contents. The slope is almost the same for all the samples at constant water to binder ratio and decreases with decreasing the water to binder ratio
