Structural Responses of Axially Restrained Steel Beams with Semirigid Moment Connection in Fire
Publication: Journal of Structural Engineering
Volume 131, Issue 4
Abstract
This paper investigates the structural responses of generally restrained steel beams under fire conditions by the finite-element method. The axial restraint is represented by a linear elastic spring, whereas the rotational restraint is simulated as a semirigid rotational spring. The developments of beam internal forces, cross-sectional stresses and strains, together with displacements are examined. Moreover, the effects of some important factors such as load utilization factor, beam slenderness ratio, and axial and flexural restraint ratios, are also studied. Numerical analyses show that the critical temperature is reduced by axial restraint but increased by semirigid rotational restraint. Some stocky beams subjected to low utilization factors buckle at elevated temperature. The later part of the paper focuses on investigating the effect of cross-sectional thermal gradient; the associated thermal bowing is detrimental for a slender beam. This paper also tabulates the finite-element (FE) predictions of the lower and upper bounds of beam critical temperature for design purposes. Besides FE analyses, the simplified methods from EC3 Pt.1.2 and BS5950 Pt.8 for critical temperature are also examined.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers would like to express their gratitude to Nanyang Technological University for the research account RG39/96 as well as the Building Construction Authority Grant CRP01/08/14.
References
Anderberg, Y. (1988). “Modelling steel behavior.” Fire Saf. J., 13, 17–26.
Bailey, C. G., Burgess, I. W., and Plank, R. J. (1996). “Computer simulation of a full-scale structural fire test.” Tanso, 74(6), 93–100.
British Standard Institution (BSI). (1987a). “Code of practice for fire resistant design: Structural use of steelwork in building.” Part 8, BS5950, London.
British Standard Institution (BSI). (1987b). British Standard BS476, Part 20: Method for determination of the fire resistance of elements of construction, London.
Chen, W. F., Goto, Y., and Liew, J. Y. R. (1996). Stability design of semi-rigid frames, Wiley, New York.
Commission of European Communities (CEC). (1995). “Design of steel structures: Part 1.2: General rules—Structural fire design (EC3 Pt.1.2).” Eurocode 3, Brussels, Belgium.
Dounas, S., and Golrang, B. (1982). Ståls mekaniska egenskaper vid höga temperaturer, Division of Building Fire Safety and Technology, Lund Institute of Technology, Lund, Sweden.
El-Rimawi, J. A., Burgess, I. W., and Plank, R. J. (1997). “The influence of connection stiffness on the behavior of steel beams in fire.” J. Constr. Steel Res., 43(1-3), 1–15.
El-Rimawi, J. A., Burgess, I. W., and Plank, R. J. (1999). “Studies of the behavior of steel subframes with semi-rigid connection in fire.” J. Constr. Steel Res., 49(1), 83–98.
Harmathy, T. Z. (1967). “A comprehensive creep model.” J. Basic Eng., 89, 469–502.
Harmathy, T. Z. (1976). “Creep deflection of metal beams in transient heating processes, with particular reference to fire.” Can. J. Civ. Eng., 3(2), 219–228.
Lawson, R. M. (1990a). “Behaviour of steel beam-to-column connections in fire.” Tanso, 68(14), 263–271.
Lawson, R. M. (1990b). “Enhancement of fire resistant of beams by beam to column connections.” Technical Rep., SCI Publication 086.
Leston-Jones, L. C., Burgess, I. W., Lennon, T., and Plank, R. J. (1997). “Elevated-temperature moment-rotation tests;on steelwork connections.” Proc. Inst. Civ. Eng., Struct. Build., 122, 410–419.
Liu, T. C. H. (1998). “Effect of connection flexibility on fire resistance of steel beams.” J. Constr. Steel Res., 45(1), 99–118.
Liu, T. C. H. (1999). “Fire resistance of unprotected steel beams with moment connections.” J. Constr. Steel Res., 51(1)61–77.
Liu, T. C. H., Fahad, M. K., and Davis, J. M. (2002). “Experimental investigation of behavior of axially restrained steel beams in fire.” J. Constr. Steel Res., 58(9), 1211–1230.
Tan, K. H., Ting, S. K., and Huang, Z. F. (2002). “Visco-elasto-plastic analysis of steel frames in fire.” J. Struct. Eng., 128(1), 105–114.
Wang, Y. C. (2002). Steel and composite structures: Behavior and design for fire safety, Spon, London.
Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 131 • Issue 4 • April 2005
Pages: 541 - 551
Copyright
© 2005 ASCE.
History
Received: Oct 9, 2003
Accepted: May 3, 2004
Published online: Apr 1, 2005
Published in print: Apr 2005
Notes
Note. Associate Editor: Venkatesh Kumar R. Kodur
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.