Experimental investigation on the dynamic behaviors of UHPFRC after exposure to high temperature. (10th December 2019)

• Record Type: Journal Article
• Authors: Yang, Yekai; Wu, Chengqing; Liu, Zhongxian; Liang, Xiangwei; Xu, Shenchun
• Is Part Of: Construction & building materials. Volume 227(2019)
• Publication Date: 2019-12-10
• Subjects: UHPFRC -- SHPB -- High temperature -- Strain-stress curve -- DIF -- SEM; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.116679
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Obtained the dynamic behavior of UHPFRC after high temperature, followed by cooling. Dynamic strength is significantly different under elevated temperatures and cooling. Scanning electron microscopy analysis and Mercury intrusion porosimetry was conducted. Abstract: Split Hopkinson pressure bar (SHPB) tests were conducted to experimentally study the dynamic behaviors of ultra-high-performance fiber-reinforced concrete (UHPFRC) after being first exposed to elevated temperatures, followed by cooling. The dynamic stress–strain relationships were measured as key parameters to study the effects of high temperature on the dynamic behaviors of fire-damaged UHPFRC. In addition, dynamic increase factor (DIF) values for the dynamic compressive strength were generated. It was found that the strength of UHPFRC increased with the increase in strain rates with high temperatures. A significant difference in the dynamic compressive strength was found under two different temperature scenarios, i.e., elevated temperatures and cooling. Scanning electron microscopy (SEM) analysis was conducted to understand the macroscopic failure phenomenon, element composition and concrete hydration process. The results provide a basis for assessing the impact resistance and anti-collapse resistance of fire-damaged UHPFRC structures.