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See detailNumerical analysis of stainless steel beam-columns in case of fire
Lopes, Nuno; Vila Real, Paulo; Simoes da Silva, Luis et al

in Fire Safety Journal (2012), 50

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See detailAxially Loaded Stainless Steel Columns in Case of Fire
Lopes, Nuno; Vila Real, Paulo; Simões da Silva, Luís et al

in Journal of Structural Fire Engineering [=JSFE] (2010), 1(1), 43-59

The simple model of Eurocode 3, for the fire resistance evaluation of stainless steel members, are based on the procedures used for carbon steel structural elements. However, due to the existing ... [more ▼]

The simple model of Eurocode 3, for the fire resistance evaluation of stainless steel members, are based on the procedures used for carbon steel structural elements. However, due to the existing differences in the constitutive laws of these two materials, it is expected that it would not be possible to use, in both materials, the same formulae for the member stability calculation, as proposed in Eurocode 3. This paper aims at increasing the knowledge on the behaviour of stainless steel axially loaded columns at elevated temperatures. For this purpose, a geometrical and material non linear computer code has been used to determine the buckling load of these elements. The Eurocode formulae are evaluated and a new proposal, that ensures accurate and conservative results when compared with the numerical simulations, is presented. [less ▲]

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See detailNumerical Modelling of Thin-Walled Stainless Steel Structural Elements in Case of Fire
Lopes, Nuno; Vila Real, Paulo; Simoes da Silva, Luís et al

in Fire Technology (2010), 46(1), 91-108

In this paper, the structural response of stainless steel thin-walled elements submitted to fire is analysed numerically by means of the geometrically and materially non-linear Finite Element program ... [more ▼]

In this paper, the structural response of stainless steel thin-walled elements submitted to fire is analysed numerically by means of the geometrically and materially non-linear Finite Element program SAFIR, including imperfections. In order to make these simulations, two main changes in the program were made: (i) the code was changed in order to deal with the stainless steel 2D material constitutive law to be used with shell elements and (ii) the possibility of the program to take into account residual stresses with shell finite elements was introduced. The stainless steel stress–strain relationship at high temperatures was based on the one presented in part 1.2 of Eurocode 3. To model the strain hardening exhibited by the stainless steels, using the shell element formulation, an approximation to the Eurocode 3 constitutive law was needed. Local and global geometrical imperfections were considered in the simulations. The paper shows the influence of the residual stresses on the ultimate load-carrying capacity of thin-walled stainless steel structural elements in case of fire. [less ▲]

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See detailLateral-torsional buckling of carbon steel and stainless steel beams subjected to combined end moments and transverse loads in case of fire
Lopes, Nuno; Vila Real, Paulo; Da Silva, Luis et al

in Kodur, Venkatesh; Franssen, Jean-Marc (Eds.) Structures in Fire. Proceedings of the Sixth International Conference (2010)

This paper presents a numerical study on the behaviour of carbon steel and stainless steel I-beams subjected to lateral-torsional buckling (LTB) in case of fire. The main motivation for this work is the ... [more ▼]

This paper presents a numerical study on the behaviour of carbon steel and stainless steel I-beams subjected to lateral-torsional buckling (LTB) in case of fire. The main motivation for this work is the fact that part 1-2 of Eurocode 3 (EC3) does not take into consideration the beneficial effect, resulting from the reduction of the plastic zones connected with non-uniform bending diagrams along the beam. Although new formulae for the LTB, that approximate better the real behaviour of steel structural elements in case of fire, have been proposed in previous works, they still do not considered the combination of end moments and transverse loads, as it is stated in part 1-1 of EC3. Therefore, in this paper numerical simulations, of steel beams with combined end moments and transverse loads, are compared with the LTB design curves of EC3, and new correction factors that improve these curves are presented. [less ▲]

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See detailLateral-torsional buckling of Stainless steel I-beams in case of fire
Vila Real, Paulo; Lopes, Nuno; Da Silva, Luis et al

Conference (2007, November 27)

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See detailStainless steel beam-columns in case of fire
Lopes, Nuno; Vila Real, Paulo; Da Silva, Luis et al

in Beale, R. G. (Ed.) proceedings of the 6th International Conference on Steel and Aluminium Structures ICSAS'07 (2007, July 25)

Eurocode 3 states that stainless steel structural members, subjected to high temperatures, must be designed with the same expressions used on carbon steel members. However, as these two materials have ... [more ▼]

Eurocode 3 states that stainless steel structural members, subjected to high temperatures, must be designed with the same expressions used on carbon steel members. However, as these two materials have different constitutive laws, it should be expected that different formulae for the calculation of member stability should be used for room temperature design. In a recent work, the authors have proposed a more accurate procedure for the evaluation of the fire resistance of stainless steel columns which necessarily affects the beam-column design formulae. This work presents a numerical study of the behaviour of stainless steel beam-columns subjected to fire. [less ▲]

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See detailStainless steel beam-columns in case of fire
Lopes, Nuno; Vila Real, Paulo; Da Silva, Luis et al

Conference (2007, July 25)

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See detailLateral-torsional Buckling of Ferritic Stainless Steel Beams in Case of Fire
Lopes, Nuno; Vila Real, Paulo; Da Silva, Luis et al

in Proceedings of the first International Conference on the Art of Resisting Extreme Natural Forces (2007, July 12)

This work presents a numerical study of the behaviour of ferritic stainless steel Ibeams subjected to lateral-torsional buckling and compares the obtained results with the beam design curves of Eurocode 3 ... [more ▼]

This work presents a numerical study of the behaviour of ferritic stainless steel Ibeams subjected to lateral-torsional buckling and compares the obtained results with the beam design curves of Eurocode 3. New formulae, for the lateraltorsional buckling, that approximate better the real behaviour of ferritic stainless steel structural elements in case of fire are proposed. These new formulae were based on numerical simulations using the program SAFIR, which was modified to take into account the material properties of the stainless steel. [less ▲]

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See detailParametric analysis of the lateral-torsional buckling resistance of steel beams in case of fire
Vila Real, Paulo; Lopes, Nuno; Simoes da Silva, Luis et al

in Fire Safety Journal (2007), 42(6-7, SEP-OCT), 416-424

Numerical modelling of the lateral-torsional buckling of steel beams at elevated temperature has shown that the beam design curve from EN 1993-1-2 is over-conservative in the case of non-uniform bending ... [more ▼]

Numerical modelling of the lateral-torsional buckling of steel beams at elevated temperature has shown that the beam design curve from EN 1993-1-2 is over-conservative in the case of non-uniform bending. Based on the newly proposed methodology for cold design from the EN 1993-1-1, an improved proposal for the lateral-torsional buckling of unrestrained steel beams subjected to fire is presented in this paper that addresses the issue of the influence of the loading type, the steel grade, the pattern of the residual stresses (hot-rolled or welded sections) and the ratio h/b, between the depth h and the width b of the cross-section on the resistance of the beam, achieving better agreement with the numerical behaviour while maintaining safety. The proposal is found to be safe and accurate through an extensive comparison with the results of FEM numerical simulations of more than 5000 beams. A statistical study of the results is performed, showing the accuracy of the improved proposal presented in this paper. (C) 2007 Elsevier Ltd. All rights reserved. [less ▲]

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See detailNumerical modelling of steel beam-columns in case of fire - comparisons with Eurocode 3
Vila Real, Paulo; Lopes, Nuno; da Silva, Luis Simoes et al

in Fire Safety Journal (2004), 39(1), 23-39

This paper presents a numerical study of the behaviour of steel I-beams subjected to fire and a combination of axial force and bending moments. A geometrical and material non-linear finite element program ... [more ▼]

This paper presents a numerical study of the behaviour of steel I-beams subjected to fire and a combination of axial force and bending moments. A geometrical and material non-linear finite element program, specially established in Liege for the analysis of structures submitted to fire, has been used to determine the resistance of a beam-column at elevated temperature, using the material properties of Eurocode 3, part 1-2. The numerical results have been compared with those obtained with the Eurocode 3, part 1-2 (1995) and the new version of the same Eurocode (2002). The results have confirmed that the new proposal for Eurocode 3 (2002) is more conservative than the ENV-EC3 (1995) approach. (C) 2003 Elsevier Ltd. All rights reserved. [less ▲]

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See detailNew proposals for the design of Steel-Beam-Colums under fire conditions
Lopes, Nuno; Vila Real, P. M. M.; Simoes da Silva, Luis et al

in Franssen, Jean-Marc; Benichou; Kodur (Eds.) et al Proceedings of SiF'04: Third International Structures in Fire workshop (2004)

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See detailLateral-torsional buckling of unrestrained steel beams under fire conditions: Improvement of EC3 proposal
Vila Real, Paulo; Lopes, Nuno; da Silva, Luis Simoes et al

in Computers & Structures (2004), 82

The final draft of the EN version of part 1.1 of Eurocode 3 has introduced significant changes in the evaluation of the lateral-torsional buckling resistance of unrestrained beams at room temperature that ... [more ▼]

The final draft of the EN version of part 1.1 of Eurocode 3 has introduced significant changes in the evaluation of the lateral-torsional buckling resistance of unrestrained beams at room temperature that reduce the over-conservative approach of ENV 1993-1-1 in the case of non-uniform bending. Numerical modelling of the lateral-torsional buckling of steel beams at elevated temperature has shown that the beam design curve from prEN 1993-1-2 is over-conservative for loadings other than uniform bending. In line with the safety format of the lateral-torsional buckling code provisions for cold design, an alternative proposal for rolled sections or equivalent welded sections subjected to fire is presented in this paper, that addresses the issue of the influence of the loading type on the resistance of the beam, achieving better agreement with the real behaviour while maintaining safety. (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailTowards a consistant safety format of steel beam-columns: application of the new interaction formulae for ambient temperature to elevated temperatures
Vila Real, Paulo; Lopes, Nuno; da Silva, Luis et al

in Steel & Composite Structures (2003), 3(6), 383-401

Two new formulae for the design of beam-columns at room temperature have been proposed into Eurocode 3, prEN 1993-1-1 (2002), and are the result of great efforts made by two working groups that followed ... [more ▼]

Two new formulae for the design of beam-columns at room temperature have been proposed into Eurocode 3, prEN 1993-1-1 (2002), and are the result of great efforts made by two working groups that followed different approaches, a French-Belgian team and an Austrian-German one. Under fire conditions the prEN 1993-1-2 (structural fire design) presents formulae, for the design of beam-columns based on the prENV 1993-1-1 (1992). In order to study the possibility of having, in part 1-1 and part 1-2 of the Eurocode 3, the same approach, a numerical research was made using the finite element program SAFIR, developed at the University of Liege for the study 4 structures subjected to fire. [less ▲]

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