Recent advances in understanding the role of supplementary cementitious materials in concrete

Fly ash-based geopolymer: clean production, properties and applications

An overview on the influence of various factors on the properties of geopolymer concrete derived from industrial by-products

Geopolymer binder and recycled aggregates are considered as the two important sustainable ingredients in concrete production. Ground granulated blast furnace slag (GGBS) and fly ash combination based geopolymeric recycled aggregates concretes (GRAC) were prepared as a substitution of normal concrete in order to reduce the consumption of ordinary Portland cement and natural aggregates as well as to make use of demolished waste concrete. The aim of this study is to investigate the combined effects of GGBS and fly ash considering water-binder (W/B) ratio on the fresh and hardened properties of alkali activated GRAC. The slump, setting time, compressive strength, stress-strain relation, elastic modulus, Poisson's ratio, toughness and failure mode of alkali activated GGBS and fly ash based GRAC containing 100% recycled coarse aggregates were experimentally examined. In addition, the hydration mechanisms were studied by XRD and SEM. Finally, the failure mechanism of this kind of novel green concrete subjected to compression was revealed. The results show that GGBS and fly ash exhibits a superior synergetic effect on the performance of GRAC, i.e. fly ash and GGBS are mainly responsible for the workability and mechanical properties, respectively. GGBS/fly ash ratio has a significant influence on the fresh and hardened properties of GRAC. Moreover, the effect of W/B ratio on GRAC strongly depends on the GGBS/fly ash ratio. GGBS content at less than 25% was found to slightly influence the consistency and compressive strength of GRAC. The combination of 50% GGBS and 50% fly ash with a 0.5 W/B ratio could provide excellent mechanical performance and workability for GRAC.

Effects of combined usage of GGBS and fly ash on workability and mechanical properties of alkali activated geopolymer concrete with recycled aggregate

Geopolymers as an alternative to Portland cement: An overview

Physical–mechanical and microstructural properties of alkali-activated fly ash–blast furnace slag blends

External sulfate attack on alkali-activated slag

Improving reactivity of fly ash and properties of ensuing geopolymers through mechanical activation

Lead immobilization by geopolymers based on mechanically activated fly ash

The influence of fly ash characteristics and reaction conditions on strength and structure of geopolymers

Violeta Nikolić

Papers

Physical–mechanical and microstructural properties of alkali-activated fly ash–blast furnace slag blends

External sulfate attack on alkali-activated slag

Improving reactivity of fly ash and properties of ensuing geopolymers through mechanical activation

Lead immobilization by geopolymers based on mechanically activated fly ash

The influence of fly ash characteristics and reaction conditions on strength and structure of geopolymers