Degradation mechanism of hybrid fly ash/slag based geopolymers exposed to elevated temperatures

As a promising alternative to alkali-activated fly ash (AAF) for high temperature application, the degradation mechanism of ash/GGBS (AAFS) under is not clear. This work investigates physicochemical properties AAFS up 800 °C and presents their synergetic influence on thermal behavior. A quantitative assessment crack developed learn cracking Results reveal that density exhibits linear relationship with ultrasonic pulse velocity. The compressive strength exhibit positive correlation before 100 °C, but negative beyond °C. addition slag into geopolymers lessons geopolymeric behaviors such as further geopolymerization viscous sintering, aggravates damage owing compact structure unstable hybrid gel. conceptual models AAF are proposed explain low contained elevated temperatures.