Rheo-morphological investigation of static and dynamic stability of self-consolidating concrete: A biphasic approach

Stability and compressive strength of 30 self-consolidating concrete (SCC) mixtures proportioned with normal and low binder contents were investigated as biphasic suspensions of fine mortars (<1.25 mm) and coarse aggregate (>1.25 mm). Static and dynamic stability of the investigated SCC mixtures were evaluated using the penetrometer and T-Box set-ups, respectively. Moreover, the morphological characteristics of different size subclasses of coarse aggregate were assessed using 3D image processing. The investigated fine mortars were characterized in terms of the visco-elastoplastic properties and compressive strength. A new lattice factor was proposed to evaluate the particles’ lattice effect on stability of SCC. On the other hand, new empirical models were proposed to evaluate the inter-particle squeeze force and drag coefficient of the irregularly-shaped coarse aggregate. According to the established correlations, among the morphological characteristics of coarse aggregate, the mean diameter and 3D surface area of coarse aggregate exhibited the most dominant effect on stability (static and dynamic) and compressive strength of SCC, respectively. From rheological point of view, the yield stress and plastic viscosity of fine mortar were found as the main viscoplastic parameters which significantly control the stability of SCC.