Behaviour of fire damaged cement and geopolymer concrete slabs under static and impact loading

Abstract

Fire is considered one of the most serious potential risks for buildings and structures, as was demonstrated in the 9/11 twin tower failure. If a structure is damaged by fire, it is necessary to investigate the cause of the fire and evaluate the reusability of the damaged structure. Concrete structures often collapse in fire due to material degradation and thermal expansion. Geopolymer concrete has the potential to reduce carbon emission globally and lead to sustainable development to form an important contributor towards environmentally sustainable construction and building products industry. It proposed to be a more eco-friendly replacement to Portland cement. The experimental results of Cement and Geopolymer concrete slabs subjected to high temperatures are presented in this study. This study exclusively focuses on assessing the load-carrying capacity of fire-damaged Cement and Geopolymer Concrete structural elements. The slab specimens were subjected to temperatures of 200, 400, 600 and 800°C for a period of 1, 2, and 3 hours. The results showed that the ultimate load-carrying capacity of both cement and geopolymer concrete slabs increased when exposed to 200ºC for 1 hour. However, beyond this point, the capacity started to decrease. Nevertheless, a decline in ultimate load capacity was noted for higher temperature ranges and prolonged fire exposure durations. When exposed to high temperature, the chemical composition and physical structure of the geopolymer concrete change considerably.