Hydration and mechanical properties of water-entrained cement-based materials

In this work, the relation between compressive strength and the hydration of waterentrained silica fume modified cement-based materials is analysed. A model developed in previous research is used to determine both pozolanic and internal curing activity. This is done taking as base-input the thermal decomposition of SF-added and plain cement-based systems. It is found that the addition of superabsorbent polymers enhances both primary and secondary reactions within hydration. There is also a clear indication that the physical properties of the cement paste influences the course of the secondary reaction. Furthermore, the compressive strength of the composites was analysed in non-restrained and in restrained systems, referring to cement pastes and cement mortars respectively. The measured compressive strength is lower in the case of water-entrained unrestrained cement-based materials. However, in restrained systems, the addition of superabsorbent polymers is beneficial. The relation between hydration degree and strength development is discussed for water-entrained cement-based materials. Further research is required to verify the degree of cracking of these systems.