Properties of self-compacting and conventional concrete – differences and similarities

The self-compacting concrete (SCC) used in Switzerland usually has a relatively low binder content and its rheological properties are characterised by a low viscosity and a high yield stress. Up to the present it has been mainly used for walls. An important condition for its application is a knowledge of the resulting properties and how they compare with conventionally vibrated concrete (CVC). In this study nine different SCC mixtures having the volume of paste and the ratio between sand and gravel as variables were compared with four different mixtures of CVC. Compressive strength, flexural strength, E-modulus, gas permeability, shrinkage and creep were measured. The relative amount of paste caused differences in the properties of the two types of concrete. SCC displayed a lower E-modulus, a higher shrinkage and higher creep rate at an identical compressive strength. Properties that are mainly controlled by the water: binder ratio such as compressive strength, flexural strength and oxygen permeability were similar for SCC and CVC.