Title:
Idealization of Bond Stress-Slip Relationship at Elevated Temperatures Based on Pullout Tests
Author(s):
Mohammad Mahdi Raouffard and Minehiro Nishiyama
Publication:
Structural Journal
Volume:
115
Issue:
2
Appears on pages(s):
391-400
Keywords:
bond mechanism; bond strength; bond stress-slip model; elevated temperatures; finite element analysis; pullout test; reinforced concrete beam
DOI:
10.14359/51701120
Date:
3/1/2018
Abstract:
To estimate the contribution of slip flexibility to the total deflection of reinforced concrete (RC) structural elements under fire conditions, adopting a temperature-sensitive bond stress-slip model in the analysis is needed. In this research, by conducting a series of steady-state pullout tests, the effect of elevated temperatures on the bond between a typical D19 ribbed bar and its confining normalweight concrete (NWC) was investigated. Based on the test results, a bond stress-slip model at elevated temperatures was statistically developed. The proposed bond-slip model was implemented into a bond-link finite element to simulate the fire responses of four fire-tested RC beams. The analyses showed an improvement in the deflection predictions compared to when the perfect bond condition was considered. However, the contribution of slip flexibility under hot conditions into the total deflections (below deflection limits) of the RC beams was minor.