Effect of High Temperature Exposure and Strain Rate on Mechanical Properties of High-Strength Steel Rebars
Abstract
In this study, quasi-static tensile tests of high-strength steel rebars, after exposure to 20°C-1,300°C, and dynamic tensile tests at a strain rate of up to 0.25 s-1, after exposure to 20°C-900°C, were conducted to understand the effect of elevated temperature and strain rate on the mechanical properties of the high-strength steel rebars. The coupled effect of high temperature exposure and strain rate was discovered; the strength equation and the constitutive model of high-strength steel rebars were proposed with the coupled effect taken into account. Specifically, the color and weight of steel rebars, after exposure to above 700°C, change significantly because of oxidation. High temperature significantly affects the fracture morphology of rebars when statically tested, but it has little effect when dynamically tested. High-strength rebars begin to degrade at 500°C with their residual yield and ultimate strength remaining greater than 60% and 70%, respectively, after exposure to temperatures above 900°C. Their strengths are affected by strain rate more significantly at higher temperatures because of microstructural changes. The hardening strain is related to both temperature and strain rate; the ultimate strain is affected by temperature only.
Recommended Citation
H. Qian et al., "Effect of High Temperature Exposure and Strain Rate on Mechanical Properties of High-Strength Steel Rebars," Journal of Materials in Civil Engineering, vol. 31, no. 11, American Society of Civil Engineers (ASCE), Nov 2019.
The definitive version is available at https://doi.org/10.1061/(ASCE)MT.1943-5533.0002906
Department(s)
Civil, Architectural and Environmental Engineering
Research Center/Lab(s)
INSPIRE - University Transportation Center
Keywords and Phrases
Constitutive model; High temperature; High-strength steel rebar; Mechanical properties; Microstructure; Strain rate
International Standard Serial Number (ISSN)
0899-1561; 1943-5533
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2019 American Society of Civil Engineers (ASCE), All rights reserved.
Publication Date
01 Nov 2019
Comments
The authors appreciate the financial support from the National Science Foundation of China (Nos. 51522905, 51778570, and 51879230), the Zhejiang Provincial Natural Science Foundation of China (No. LR15E090001), and the Fundamental Research Funds for the Central Universities (No. 2019QNA4044).