Effect of Sustained Service Loading on Post-Fire Flexural Response of Reinforced Concrete T-Beams

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Effect of Sustained Service Loading on Post-Fire Flexural Response of Reinforced Concrete T-Beams

Author(s): Chanachai Thongchom, Akhrawat Lenwari, and Riyad S. Aboutaha

Publication: Structural Journal

Volume: 116

Issue: 3

Appears on pages(s): 243-254

Keywords: elevated temperatures; finite element analysis; fire damage; flexural response; reinforced concrete beams; sustained service loading; thermal response

Date: 5/1/2019

Abstract:
This paper presents the effect of sustained service loading at elevated temperatures on the residual flexural response of reinforced concrete (RC) T-beams after exposed to elevated temperatures of 700 and 900°C (1292 and 1652°F) for 3 hours and then cooled in air. Two beams were subjected to a constant simulated service loading equal to 22.6% of undamaged (unheated) flexural strength, while the counterpart beams were exposed to fire without any applied sustained load. The test results showed that the bottom (tension) steel reinforcements in all fire-exposed beams had experienced the peak temperatures that were higher than a critical value (593°C [1099°F]) before the post-fire static test. The post-fire static test results showed that the sustained loading has a detrimental effect on the post-fire flexural response of RC beams. The effect was more pronounced on the post-fire stiffness and ductility than on strength. In the paper, simplified finite element models for predicting the temperature response and post-fire load-deflection relationships of fire-exposed RC beams are also described.