"Flexural Performance of Hybrid Fiber Reinforced Cement Composites Under Elevated Temperatures"

"Historically, the flexural behavior of hybrid fiber cement composites is not completely understood using the traditional test methods. This research presents the results of an experimental investigations on a high performance cement composites (HPCC) containing both micro steel fibers (SF) and micro polypropylene fibers (PP) before and after elevated temperature exposure. The experimental program was developed to study the flexural performance (flexural strength, toughness and stiffness) under high temperature using mono and hybrid (SF) and (SF + PP) fibers. Mixtures were divided into eight different groups, with constant w/c of 0.28 and different fibers content. Based on the results of this research, the replacing of micro (SF) in high performance cement composites by 15 % of micro (PP) fibers is recommended at high temperature exposure due to the fact that all hybrid fiber HPCC specimens show slight decreasing in flexural behavior compared to samples reinforced with 1% volume fraction of mono steel fibers after high temperature exposure."