ABSTRACT
Due to the relatively low water-cement ratio values, concrete from stiff mixtures hardens faster, especially at the early stages. The low water demand of such concrete is due to the fact that it has a fine porous structure that holds water, especially when heated. For Vibro-Pressed Fine Grained Concrete (VFC) the initial horizontal section is not characteristic—the change in the ultrasonic waves passage velocity occurs smoothly with the transition to the highest velocity. Effectiveness of adding a filler into stiff concrete mixtures compacted by vibro-pressing was also reported for a fine-grained perlite-concrete mixture with fly ash to ensure better products molding. To study the granite filler influence on vibro-pressed cement stone hydration degree, cylindrical specimens were made which were compacted for 15 seconds under a load of 0.06 mega pascal. This chapter studies kinetics of water chemical binding in a cement stone, depending on the dusty fraction content in granite siftings.
