Calculation of Relative Thermal Elongation of Structural Steels

Published

May 2, 2009

Author(s)

Dilip K. Banerjee, Ursula R. Kattner

Abstract

In the recent past, there has been a number of studies toward predicting the thermal and structural behavior of components subjected to elevated temperature due to an exposure to fire. Numerical modeling has been applied quite extensively toward this end. An accurate numerical model requires the use of appropriate thermophysical properties of the materials such as steels, concretes etc. Recent investigations to the collapse of World Trade Center 7 building showed that thermal expansion coefficient played an important role in the generation of stresses at elevated temperatures in components that are restrained structurally [1]. In this paper, relative thermal elongations of structural steels are computed using an approach similar to the one proposed by Andres [1] but with a novel method of computing volume phase fractions using a thermodynamic database in conjunction with Thermo-Calc. Thermal expansion coefficient values were computed for a steel of eutectoid composition and an ASTM A572 Grade 50 steel. While the volume fractions of phases for A572 steel were computed using thermodynamic approach, those for the eutectoid steel were computed using an approach similar to the one proposed in reference [2]. The computed values of relative thermal elongation were compared with the values obtained from Eurocode. While the match was reasonable for the most part, there are significant differences in the values obtained during the phase transformation range.

Citation

Journal of Materials Science

Pub Type

Journals

Keywords

Relative thermal elongation, thermal expansion, modeling, CALPHAD, phase equilibria

Citation

Banerjee, D. and Kattner, U. (2009), Calculation of Relative Thermal Elongation of Structural Steels, Journal of Materials Science (Accessed April 29, 2024)