Fire performance and characterization of geopolymer foams using fly ash and coal gangue

Abstract

The paper introduces foamed geopolymers as effective thermal insulation materials for buildings, with the ability to withstand high temperatures. The production methods for achieving a porous microstructure in geopolymers are discussed, emphasizing the use of foaming agents like aluminium powder. The presented research focuses on developing geopolymer foams from industrial waste materials [fly ash and coal gangue] with enhanced thermal and fire resistance while maintaining robust mechanical properties. The novelty lies in evaluating these foams at a medium-sized panel scale [750 mm x 750 mm x thickness] and assessing their fire resistance through comprehensive tests, differentiating it from existing literature that primarily explores smaller-scale materials. Class F fly ash from Skawina power plant, Poland and waste rock from coal mining KWK Wieczorek, Katowice, Poland were used for preparation of geopolymer foam. The research aims to contribute insights into the fire performance of geopolymer foams under ISO 834-1 fire scenario, paving the way for potential applications as thermal insulation panels in building facilities. Results from fire exposure tests, post-fire mechanical property assessments, SEM observations, EDS analyses, XRD analyses, as well as ageing effects are presented and discussed. While foamed geopolymers demonstrate resilience and fire resistance, variations in their mechanical properties and microstructure due to fire exposure are highlighted. The research underlines the potential of employing geopolymer foams as a sustainable solution for thermal insulation in construction, opening up further exploration and application in the construction industry.