2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Ahmed Soliman, Concordia University
This study investigates the influence of varying the concentration of sodium oxide (Na2O) and activator modulus (Ms) i.e. SiO2/Na2O on workability and mechanical properties of various alkali-activated self-consolidating concrete (AASCC) mixtures. Three Na2O dosage levels (i.e. 4%, 6% and 8%) in addition to SiO2/Na2O ratios (i.e. 1, 1.25 and 1.5) of the alkaline solutions were considered in the study. Fresh and mechanical properties including L-Box, inverted slump test, compressive and tensile strengths, and modulus of elasticity were evaluated for all mixtures. Moreover, representative samples from optimal mixtures were examined using differential scanning calorimetry (DSC), scanning electron microscope (SEM) and X-ray diffraction (XRD). Results indicated an increase in the mechanical properties was observed while increasing the Na2O concentration and Ms ratio, yet the workability decreased.
Keywords: Alkali-activated concrete, self-consolidating concrete, workability, SEM