Development of ultra-high performance concrete with high fire resistance. (10th August 2018)

• Record Type: Journal Article
• Authors: Liang, Xiangwei; Wu, Chengqing; Su, Yu; Chen, Zhu; Li, Zhongxian
• Is Part Of: Construction & building materials. Volume 179(2018)
• Page Start: 400
• Page End: 412
• Publication Date: 2018-08-10
• Subjects: Ultra-high performance concrete -- Fire resistance -- Steel slag -- Steel fibre -- Polypropylene fibre -- Elevated temperature; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2018.05.241
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Exposed to 1000 °C, the UHPC retained 69% of its original compressive strength. Steel slag played a key role in improving fire resistance of the UHPC. Mass loss of the UHPC mixtures mostly occurred between 200 and 400 °C. Abstract: Fire or high temperature is a big challenge to ultra-high performance concrete (UHPC). Strength loss of UHPCs can reach up to 80% after exposure to 800 °C. In this study, a total of six UHPC mixtures were designed and tested after subjected to elevated temperatures up to 1000 °C. The effects of aggregate type, fibre type and heating rate were investigated. Residual compressive strengths and stress-strain relationships were studied. Besides, attention was paid to explosive spalling since UHPCs are usually of compact structure and thus more vulnerable to explosive spalling than other concretes. Scanning electron microscope (SEM) analysis was conducted to help understand the mechanism of variation of internal structure under different temperatures. It was found the mixture containing steel slag and hybrid fibre had excellent fire resistance. After being subjected to 1000 °C, this mixture retained a residual compressive strength of 112.8 MPa or a relative value of 69%.