Title:
Reliability of Temperature-Dependent Models for Analysis of Reinforced Concrete Members Subjected to Fire
Author(s):
Fady ElMohandes and Frank J. Vecchio
Publication:
Structural Journal
Volume:
113
Issue:
3
Appears on pages(s):
481-490
Keywords:
ASCE; cooling; Eurocode; fire; heat; structures; thermal
DOI:
10.14359/51688605
Date:
5/1/2016
Abstract:
A computational modeling procedure has been developed for better estimating the behavior of reinforced concrete members subjected to fire. The highly nonlinear procedure of combined thermal and structural analysis integrates the transient conductive, boundaryconvective, and boundary-radiative heat transfer analysis with the structural analysis of reinforced concrete members. The effect of the models selected for the various temperature-dependent properties of concrete and steel reinforcement on the overall response of reinforced concrete members with various loading and fire scenarios was studied. For concrete materials, the temperaturedependent properties investigated and included the density, thermal conductivity, specific heat capacity, thermal expansion strain, peak compressive stress and the corresponding strain, initial modulus of elasticity, tensile strength, and the shape of the stress-strain curve. For steel reinforcing bars, they included the thermal expansion strain, yield stress, ultimate stress, and Young’s modulus. In addition to the heat development phase, the cooling phase was also considered as a fire scenario, where the residual capacity of concrete columns subjected to fire was investigated.
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