Characterization and performance of high volume recycled waste glass and ground granulated blast furnace slag or fly ash blended mortars

The application of recycled waste glass powder in high volume (60%) of ground granulated blast furnace slag (GGBS) or fly ash blended cement binder is shown in this study. The hydration kinetics, hydration products of different binder systems were studied by calorimetric and X-ray diffraction test. To investigate the microstructure properties of bended binders modified by glass powder, the mercury intrusion porosimetry test and scanning electron microscopy were conducted. The resistance to chloride penetration was evaluated by the rapid chloride migration test. The incorporation of recycled waste glass in slag or fly ash blended cement improves the reaction intensity while decreases the duration of induction period. The calcium hydroxide content of blended samples (91 days) was decreased after the incorporation of waste glass powder, while a densification effect on the capillary pores (10-100 nm) and lowers the total porosity of waste glass containing ternary binders were observed. From the SEM analysis, a dense microstructure and inter transition zone can be found in recycled waste glass blended samples. The waste glass powder modified slag or fly ash blended mortars exhibit a significant enhancement of resistance to chloride migration. Furthermore, a synergistic effect on the mechanical performance of large volume GGBS blended mortars containing recycled waste glass was identified, which presented the highest compressive strength among all waste blended samples. (C) 2019 Elsevier Ltd. All rights reserved.