High-strength high-performance concrete incorporating different macro fiber types and contents: Engineering and durability performance

Abstract

ABSTRACTGenerating a synergistic response by combining the advantages of different fiber types in concrete is of current scholarly interest. This study investigated the effects of different hooked-end steel fiber (SF) volume fractions up to 1.6% and three macro fiber types including polypropylene (PP), SF, and typical hybrid fibers (HF: 50% SF + 50% PP) at a fixed dosage of 1.6% on properties of high-strength high-performance concrete (HSHPC). A novel densified mixture design algorithm was used to incorporate a high quantity of fly ash and rice husk ash as an eco-binder. Results showed the specimens with added macro SF exhibited improved mechanical strength, dynamic modulus of elasticity and rigidity, and lower drying shrinkage while the ones with added PP exhibited reductions in compressive strength and dynamic modulus. Interestingly, the incorporation of macro fibers, regardless of fiber type and content, reduced electrical resistivity, ultrasonic pulse velocity and increased the total charge passed in the chloride ion penetration test, resulting in likely underestimation of the reinforcement corrosion resistance, especially for SF specimens. The findings also confirm that HF demonstrating synergistic response may be effective and creative in improving most of the concrete characteristics, contributing to the efficient use of HSHPC in real-world structures.CO EDITOR-IN-CHIEF: OuYu-ChenASSOCIATE EDITOR: OuYu-ChenKEYWORDS: Macro fiberhybrid fiberhigh-strength high-performance concreteengineering propertiesdurability performance Nomenclature ACI=American Concrete InstituteDMDA=Densified Mixture Design AlgorithmER=Electrical ResistivityFA=Fly AshFRC=Fiber-Reinforced ConcreteHPC=High-Performance ConcreteHF=Hybrid FiberHPFRC=High-Performance Fiber Reinforced ConcreteHSC=High-Strength ConcreteHSHPC=High-Strength High-Performance ConcreteOPC=Ordinary Portland CementPP=Polypropylene FiberRCPT=Rapid Chloride ion Penetration TestRHA=Rice Husk AshSCC=Self-Compacting ConcreteSCM=Supplementary Cementitious MaterialsSF=Steel FiberSP=SuperplasticizerUPV=Ultrasonic Pulse VelocityAcknowledgmentsThe samples used for this study were prepared at the Construction Material Research Laboratory of the National Taiwan University of Science and Technology with valuable assistance from Dr. Duy-Hai Vo.Disclosure statementNo potential conflict of interest was reported by the author(s).