A Study of the Behaviour of Hybrid-fiber Reinforced High-strength Concrete under Elevated Temperatures

Project: Research

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Description

Concrete spalling in fire, closely related to the initiation and growth of cracks which lead to eventual detachment of portions of concrete from RC structures, is a major fire safety concern. Recently, with the addition of low melting point fibre such as polypropylene (PP) fiber in high-strength concrete (HSC), possibility of spalling will be decreased but with reducing residual strength, while the addition of high melting point fibre such as steel fiber increases the residual strength but not reducing spalling of HSC in fire situations. In this research, the adding of the hybrid-fiber (HFR) with the mixing of high melting point fiber (i.e. carbon or steel fiber) and low melting point fiber (i.e., PP fiber) to HSC is proposed which aimed to greatly improve the properties of HSC after exposure to high temperatures. Although theoretical analyses and numerical simulations have explicitly revealed the high temperature effect on microstructure, bond strength and coupled constitutive model of normal concrete, none of these are available for HFR-HSC. In this proposed research, the mechanical behavior, microstructure transforming, chemo-elastoplastic-damage constitutive and bond-slip relationship of HFR-HSC will be studied. The numerical calculations on the structure components of HFR-HSC structure at high temperature will be performed. Comparison work between numerical result and the tests will be involved in the investigation, and the result will be evaluated.

Detail(s)

Project number7002577
Grant typeSRG
StatusFinished
Effective start/end date1/05/1019/04/13