New methodology to evaluate the Reynolds dilatancy of self-consolidating concrete using 3D image analysis - Coupled effect of characteristics of fine mortar and granular skeleton

Abstract

The shear-induced volumetric change of 30 self-consolidating concrete (SCC) mixtures with normal and low binder contents was investigated using a coaxial-cylinders tribometer. A new methodology to evaluate the Reynolds dilatancy of SCC using 3D image analyses was proposed. This consisted in assessing the changes in elevation of the free surface of concrete before and after shearing. The flowability and passing ability of the investigated SCC mixtures were evaluated by slump flow, V-Funnel, L-Box, and J-Ring test set-ups. SCC mixtures were considered as a diphasic suspension of a visco-elastoplastic fine mortar (<1.25 mm) and coarser portion of granular skeleton (>1.25 mm).The Reynolds dilatancy measurements were found to be in good agreement with workability of SCC. The coupled effect of the shear rate, relative coarse solid packing fraction of aggregate, and visco-elastoplastic properties of fine mortar on Reynolds dilatancy values were evaluated. Furthermore, the thickness of the lubrication layer in tribology tests was estimated using the results of the proposed Reynolds dilatancy methodology.