PORE STRUCTURE AND STRENGTH DEVELOPMENT OF CEMENT COMPOSITES

Two stages are to be distinguished in the development of cement composite pore structure. The first stage is determined by the composition of the mixture as well as by its mixing efficiency and compaction degree. During this stage the initial pore structure, characterized by the initial porosity - P, is being formed. The second stage of the pore structure deve⌉opment is a consequence of the hydration products creation in hardening cement composite. In dependence on the volume as well as on the kind, morphology and other properties of the created hydration products the total porosity diminishes, the hydration micropores arise and the final pore structure -with a characteristic pore size distribution and micropores shape- is formed. A close relationship between the pore structure and strength of cement based composites follows from the fact that both these properties depend decisively on the volume, kind and other parameters of hydration products created. © 1990.