Abstract
Various parameters influencing consistency of fresh concrete and mortar and are utilized for predicting workability. Those parameters are ratio of paste volume to void content of densely compacted aggregate phase, free water content, surface area, shape and water retainability of aggregates and powder materials. It was found that slump of concrete varied linearly with free water, but non-linearly with other parameters. A mathematical model for predicting flow spread of mortar and slump of concrete was formulated and verified with the actual results. It was found that the model could be used for concretes and mortars made from various types of powder material, however, without chemical admixture with satisfy accuracy.
