Plastic capacity of semi-compact steel sections

in Proceedings of the CIMS2008 - Coupled Instabilities in Metal Structures (2008, June)

A new design model for the resistance of steel semi-compact cross-sections

in Proceedings of EUROSTEEL 2008 (2008)

Design of beam-columns in steel sway frames: from the actual member to a simply supported equivalent one

in Proceedings of the 2007 Annual Technical Stability Conference, Structural Steel Research Council (2007)

Experimental and numerical investigations for I-girders in bending and shear stiffened by closed trapezoidal stiffeners for use in steel bridges

in Proceedings of the IABSE Symposium "Improving infrastructures..." (2007)

The paper summarizes the investigations on shear resistance of I-girders longitudinally stiffened by closed trapezoidal stiffeners, performed in the frame of a European RFCS project (RFS-CR-03018 ... [more ▼]

The paper summarizes the investigations on shear resistance of I-girders longitudinally stiffened by closed trapezoidal stiffeners, performed in the frame of a European RFCS project (RFS-CR-03018) designated as “ComBri” (Competitive Steel and Composite Bridges by improved Steel Plated Structures), with configurations typical of what may be expected in the design of modern steel bridges. It first reports on four full-scale tests performed at RWTH Aachen, on stiffened panels with strong closed stiffeners where the deformations have been measured with photogrammetric devices. As expected, failure in the subpanels has been governing. A devoted FEA shell model is then described and validated towards these results and other experimental sources. The numerical simulations demonstrate a very good agreement with the test-results. Parametric studies performed with a sophisticated numerical tool help pointing out several aspects where the recommendations of EN 1993-1-5 [1] on stiffened panels in bending and shear may be improved. [less ▲]

Experimental and numerical investigations for I-girders in bending and shear stiffened by closed trapezoidal stiffeners

in Proceedings of the ICMS Conference (2006)

The paper investigates the shear resistance of I-girders longitudinally stiffened by closed trape-zoidal stiffeners. It first reports on 4 full-scale tests performed at RWTH Aachen, on stiffened panels ... [more ▼]

The paper investigates the shear resistance of I-girders longitudinally stiffened by closed trape-zoidal stiffeners. It first reports on 4 full-scale tests performed at RWTH Aachen, on stiffened panels with strong closed stiffeners. As expected, failure in the subpanels has been governing. A devoted FEA shell model is then described and validated towards these results and other experimental sources. Parametric stud-ies led with the numerical tool help pointing out several aspects where the Eurocode 3 Part 1.5 recommenda-tions on stiffened panels in bending and shear may be improved. [less ▲]

A non-linear 3D beam finite element for the study of steel frames with tapered members

in Mota Soares, C. A. (Ed.) Proceedings of the 3rd European Conference on Computational Mechanics, Solids, Structures and Coupled Problems in Engineering (2006)

This paper presents the essentials of an original geometrically and materially nonlinear 3-D tapered beam finite element. The theoretical bases of the element are described, with particular attention paid ... [more ▼]

This paper presents the essentials of an original geometrically and materially nonlinear 3-D tapered beam finite element. The theoretical bases of the element are described, with particular attention paid to the choice of an appropriate displacement field and to the corresponding non-linear axial strains. Specific numerical problems met in the development of the finite element are examined, concerning mainly shear and membrane locking and the handling of rigid body motions. Worked examples on isolated members are presented for various types of analyses: elastic linear, elastic critical and geometrically and materially non-linear analyses. Good accuracy with reference to numerical results is shown, as well as good convergence properties. It is also demonstrated – analytically and numerically – that the use of prismatic beam finite elements for the analysis of tapered beams (segmentation technique) may lead to significant discrepancies when the behaviour is influenced by torsional aspects. Then, the behaviour of two different portal frames with tapered members is proposed, and the results obtained using shell elements, tapered beam elements and prismatic beam elements are compared. This comparison shows that the use of tapered elements leads to results in close agreement with those obtained by shell elements, unlike the prismatic ones. The convenience of the tapered beam element is also highlighted since the total number of degrees of freedom required is significantly reduced compared to a shell modelling, leading to easier meshing, shorter computation time and easier interpretation of results. [less ▲]

Rules for Member Stability in EN 1993-1-1: Background documentation and design guidelines

Book published by ECCS European Convention for Constructional Steelwork (2006)

This volume intends at helping in the understanding of the new design rules for member stability in Eurocode 3 Part 1.1 (EN 1993-1-1:2005). In particular, the new recommendations for lateral torsional ... [more ▼]

This volume intends at helping in the understanding of the new design rules for member stability in Eurocode 3 Part 1.1 (EN 1993-1-1:2005). In particular, the new recommendations for lateral torsional buckling and beam-column stability in chapter 6.3.3 (4) of Eurocode 3 are concerned. It is divided into two independent parts A and B. Part A, devoted to the background of the proposed formulae, gives further information on the way the formulae have been built and validated. Moreover, the different basic concepts used in the formulae are detailed, for the two sets of formulae proposed in the code. It is to be noted that a great number of papers prepared within the development of the formulae are made available by means of a CD-Rom that is part of this publication. Part B is dedicated to practitioners; it contains fully detailed worked examples on isolated members, from basic situations to the most complex one. In addition, an example of design of a member extracted from a frame is also given. Furthermore an annex shows especially the determination of the elastic lateral torsional buckling moment for different loading and support conditions. [less ▲]

Development of a general method for the verification of composite beams against lateral torsional buckling in the erection phase

in Proceedings of the 2005 Eurosteel Conference on Steel and Composite Structures (2005)

Improvement of the interaction formulae for beam columns in Eurocode 3

in Computers & Structures (2002), 80(27-30), 2375-2385

This paper presents a new proposal for beam-column interaction formulae initially based on second-order in-plane elastic theory, as an alternative to those proposed in the Eurocode 3 pre-standard [1]. It ... [more ▼]

This paper presents a new proposal for beam-column interaction formulae initially based on second-order in-plane elastic theory, as an alternative to those proposed in the Eurocode 3 pre-standard [1]. It has been derived according to the following requirements: theoretical background, clear physical meaning, consistency with the other related formulae of Eurocode 3 and accuracy. Besides that, the suggested formulae cover all required continuities: between the cross-section classes, from plasticity to elasticity as slenderness and axial force increase, and continuity between all the individual stability member checks and cross-section verifications. Further to the presentation of the formulae and their background, the good agreement of the proposal is shown through an extensive comparison with more than 15,000 results of finite element numerical simulations. (C) 2002 Civil-Comp Ltd. and Elsevier Science Ltd. All rights reserved. [less ▲]

The interaction formulae for beam-columns: a new step of yet long story

in Proceedings 2001 of the SSRC Annual Technical Session and Meeting (2001)