Localized fire tests on steel beams with different end restraints

Published

November 1, 2017

Author(s)

Selvarajah Ramesh, Mina S. Seif, Lisa Choe

Abstract

Two 6.2-m span I-shaped structural steel beams were tested under combined structural and open flame localized fire loads. Two different support conditions for the beam ends were considered: (i) simple support, and (ii) double-angles bolted to laterally braced support columns. A four- point flexural loading scheme was used such that two concentrated forces were applied 2.44 m apart around midspan. The beam specimens were laterally braced at the location of concentrated forces. The midspan of each specimen, i.e. expected plastic hinge zone, was exposed to an open- flame fire using natural gas burners. The measurements included heat release rate and applied forces as well as thermal and structural responses to fire. Since the thermal gradients developed in the fire-exposed cross sections induced thermal bowing, both beam specimens exhibited similar deformational behavior and failure mode regardless of their end conditions. However, the presence of end restraint, provided through the double-angles on the second specimen, decreased its fire resistance (i.e. the failure time and failure temperature).

Conference Dates

November 1-4, 2017

Conference Location

Jeju, KR

Conference Title

The 9th International Symposium on Steel Structures

Pub Type

Conferences

Download Paper

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Keywords

Fire, End restraints, Steel beams, Experimental

Citation

Ramesh, S. , Seif, M. and Choe, L. (2017), Localized fire tests on steel beams with different end restraints, The 9th International Symposium on Steel Structures, Jeju, KR, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923661 (Accessed October 13, 2025)