Splitting strength of GGBFS concrete incorporating with steel fiber and polypropylene fiber after exposure to elevated temperatures

摘要

Experiments were carried out to investigate the splitting properties of fiber reinforced ground granulated blast furnace slag (GGBFS) concrete after exposure to elevated temperatures. Based on experimental observation, the effect of GGBFS content, steel fiber dosage, polypropylene (PP) fiber dosage and strength grade of concrete on the residual splitting strength of the concrete after being subjected to high temperature was systematically analyzed. Test data indicated that high temperature caused significant deterioration in the splitting strength of concrete; the addition of GGBFS, PP fiber and steel fiber could all effectively improve the residual splitting properties of concrete; the optimum amount of GGBFS, PP fiber and steel fiber were identified, respectively; the degree of strength loss of concrete with different strength grades was very close to each other. A set of theoretical equations was proposed to predict the residual splitting strength of concrete after being heated to temperatures up to 800 ℃.