Assessing the durability performance of geopolymer concrete utilizing fly ash and sugarcane bagasse ash as sustainable binders

Abstract

Geopolymer or alkali-activated binders are being recognized as an eco-friendly, sustainable substitute for ordinary Portland cement (OPC). The development of high-performance concrete with improved durability and mechanical properties and the addition of environmentally friendly components is a continuous effort. Therefore, the current work examines the durability of fly ash-sugarcane bagasse ash mechanical characteristics in terms of water absorption, exposure to elevated temperatures, and acid resistance. The mechanical properties of the geopolymer concrete (GPC) and OPC concrete specimens were evaluated after being subjected to elevated temperatures of 200 °C, 400 °C, 600 °C, and 800 °C. The acid resistance was determined by submerging the concrete specimens in 3 % sulfuric acid (H₂SO₄). The acid resistance of the specimens was evaluated through visual inspection, weight variation, and the percentage loss in compressive strength (C_R). According to the study, C_R typically drops as temperature increases from ambient temperature to 800 °C. However, the rate of decline reduced as temperature increased from ambient temperature to 200 °C. Moreover, the GPC specimens showed a strength loss between 13 % and 21 % following 28 days of sulfuric acid immersion. In contrast, exposure to sulfuric acid caused a 51 % drop in strength for the OPC concrete samples.