The effect of clinker aggregate on acid resistance in prepacked geopolymers containing metakaolin and quartz powder in the presence of ground blast furnace slag

Climatic change and global warming occurred due to CO2 emitting from cement manufacturing are increasing rabidly, and attention is paid to produce and improve geopolymer concrete with waste materials (fly ash, silica fume) and by-product material (ground granulated blast furnace slag). The aim of this research is to identify the performance of geopolymer concrete containing metakaolin (MK) for 100 kg/m3, 200 kg/m3, and 250 kg/m3, and the quartz powder (QP) for 100, 200, and 300 kg/m3, as sand replacement in the presence of ground blast furnace slag GBFS in clinker prepacked geopolymers. Four groups of specimens are studied involves: two groups incorporating QP and MK cured at 45 °C, and two groups are cured at 75 °C. The physical and mechanical properties are studied at conventional conditions. Moreover, the compressive strength and the mass loss are investigated for all the mixes not only exposed to 350 °C and 700 °C, but also the samples subjected to acids; hydrochloric acid (HCl), sulphuric acid (H2SO4), and nitric acid (HNO3). The findings showed that, increasing QP content up to 300 kg/m3 has a positive effect in improving geopolymer concrete properties, for all curing regimes. Withal, the metakaolin addition, contributes significantly in the strength performance, but the optimum strength is obtained at 200 kg/m3 replacement. The samples cured at 75 °C enhanced the absorption resistance, mechanical properties, unit weight, high-temperature resistance, and acids’ reissuance, as well. A striking strength improvement was obtained for 42% and 68% quartz powder addition at 45 °C and 75 °C, respectively. Moreover, the strength is doubled for metakaolin addition at high temperature curing. The strength variations through presence of acids are also observed as prominent decrements, as expected. •Geopolymer prepacked concrete are noticed expansion, internal pores, and low strength, when exposed to acidic solutions.•Prepacking aggregate in geopolymer concrete is a successful way to gain high strength.•The worst microstructure exhibit in case of HNO3 with more pores and less CSH.