WIT Press


Analysis Of A Portal Steel Frame Subject To Fire By Use Of A Truss Model

Price

Free (open access)

Volume

46

Pages

11

Published

2004

Size

797 kb

Paper DOI

10.2495/HT040461

Copyright

WIT Press

Author(s)

P.G. Papadopoulos & A. Mathiopoulou

Abstract

A plane steel frame is simulated by a truss model. The bars obey uniaxial elastoplastic stress-strain laws. Yield stress and modulus of elasticity are assumed constant up to 300°C and then linearly decreasing up to zero for 900°C. Semi-rigid beam-column connection is represented by a hinge and a bar connecting column and beam; this bar has a small length and properly selected cross-section area and elasticity modulus. Three fire scenarios are considered. Numerical experiments show that heat conduction time in steel is very short and can be ignored; it is enough to assume simplified temperature distributions over the cross-sections. A short computer program, with only about 200 Fortran instructions, is documented, for the step-by-step nonlinear structural analysis of plane truss models of steel frames

Keywords