Effect of High Temperature Exposure and Strain Rate on Mechanical Properties of High-Strength Steel Rebars
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.
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
Civil, Architectural and Environmental Engineering
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)
Article - Journal
© 2019 American Society of Civil Engineers (ASCE), All rights reserved.
01 Nov 2019