The performance of a blended PFA/GGBS alkali-activated concrete using a silica fume-based activator
type: CreativeWork
description: The construction industry is currently tackling a serious concern with the ever-increasing use of Portland cement and associated carbon emissions due to urban development expansion worldwide. Hence, extensive research has been undertaken into ‘’’cement-free’’ alternative concrete has emerged in the academic and commercial space also known as alkali-activated concrete, bringing CO2 reductions of up to 85%. AAC has been elevated as a viable solution detrimental to the ‘sustainable toolkit’ for low-carbon concrete solutions through the use of various industrial and agricultural waste, chemically activated using an alkali source. Nevertheless, sodium silicate is an attractive ‘alkali activator’ but has been reported to contribute up to 75% of the total embodied carbon in AAC. This research reports on the development of an eco-friendly alternative (sodium silicate) activator derived from industrial waste (Silica Fume) and sodium hydroxide, with a key focus on providing comparison analysis with commercial sodium silicate and sodium hydroxide solutions. In doing so, various pulverised fuel ash and ground granulated blast furnace slag blends were investigated as a replacement binder to Portland cement among number activator dosages, w/b ratios, workability retaining admixture dosages on the short (compressive strength, workability, setting time) and long term (compressive strength, workability retention (2 hours), tensile splitting strength, flexural strength and elastic modulus) properties of concrete and mortar, adopting an experimental based optimum performance testing procedure. The innovative silica fume derived activator (Regime B) chemically activating PFA: GGBS mix compositions (50PFA: 50GGBS, 40PFA: 60GGBS, 30PFA: 70GGBS, 20PFA: 80GGBS) combined with a range of water-to-binder ratio’s 0.40, and 0.42 showed promising results from a minimum performance perspective (≥ C32/40 compressive strength class under BS 8500:2019, S4 consistency slump class BS EN 12350-2 and a …
abstract: The construction industry is currently tackling a serious concern with the ever-increasing use of Portland cement and associated carbon emissions due to urban development expansion worldwide. Hence, extensive research has been undertaken into ‘’’cement-free’’ alternative concrete has emerged in the academic and commercial space also known as alkali-activated concrete, bringing CO2 reductions of up to 85%. AAC has been elevated as a viable solution detrimental to the ‘sustainable toolkit’ for low-carbon concrete solutions through the use of various industrial and agricultural waste, chemically activated using an alkali source. Nevertheless, sodium silicate is an attractive ‘alkali activator’ but has been reported to contribute up to 75% of the total embodied carbon in AAC. This research reports on the development of an eco-friendly alternative (sodium silicate) activator derived from industrial waste (Silica Fume) and sodium hydroxide, with a key focus on providing comparison analysis with commercial sodium silicate and sodium hydroxide solutions. In doing so, various pulverised fuel ash and ground granulated blast furnace slag blends were investigated as a replacement binder to Portland cement among number activator dosages, w/b ratios, workability retaining admixture dosages on the short (compressive strength, workability, setting time) and long term (compressive strength, workability retention (2 hours), tensile splitting strength, flexural strength and elastic modulus) properties of concrete and mortar, adopting an experimental based optimum performance testing procedure. The innovative silica fume derived activator (Regime B) chemically activating PFA: GGBS mix compositions (50PFA: 50GGBS, 40PFA: 60GGBS, 30PFA: 70GGBS, 20PFA: 80GGBS) combined with a range of water-to-binder ratio’s 0.40, and 0.42 showed promising results from a minimum performance perspective (≥ C32/40 compressive strength class under BS 8500:2019, S4 consistency slump class BS EN 12350-2 and a …
author: Ayres, Andrew John
language: eng
date published: 2025
date modified: 2026-07-24T04:39:57Z
provider: University of South Wales
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of South Wales