René Maquoi

New design rules for plated structures in Eurocode 3

Abstract This paper gives an overview of Eurocode 3 Part 1.5 Design of Steel Structures. Supplementary rules for planar plated structures without transverse loading have been developed together with the Eurocode 3-2 Steel bridges. It covers stiffened and unstiffened plates in common steel bridges and similar structures. This paper presents the background and justification of some of the design rules with focus on the ultimate limit states. The design rules for buckling of stiffened plates loaded by direct stress are presented and explained. For shear resistance and patch loading the new rules are briefly derived and compared with the rules in Eurocode 3-1-1. Finally, the statistical calibration of the rules to tests is described.

Stability of plates and plated structures: General Report

Abstract This paper is aimed at presenting two main aspects of the design rules of Part 1.5 of ENV 1993-3 (ENV 1993-1-5. Eurocode 3–Design of steel structures: part 1.5: Supplementary rules for planar plated structures without transverse loading. Brussels: CEN, 1997), which result from some research efforts conducted in the last decade. Also some background to these rules is given. First, the resistance of plates subjected to direct stresses is examined. It is based on the consideration of two types of behaviour (platelike and columnlike behaviour) with a possible interaction between both. The general procedure can be simplified a bit when there are a very few number of longitudinal stiffeners. Second, the resistance to shear stresses of an unstiffened plate as well as the effect of longitudinal stiffeners are commented on. The fatigue resistance to web breathing is a topic that is not satisfactorily covered by the codes. However, substantial progress was achieved in the field, and this is briefly commented on. When design rules are concerned, not only are they reported on, but also a critical evaluation is made and possibly some tracks are proposed in order to improve them.

Experimental study of the non-linear behaviour of beam-to-column composite joints

Abstract This paper presents the main results of experimental research recently performed at the University of Liege, the aim of which was to analyse the behaviour up to collapse of strong-axis beam-to-column composite joints commonly used in practice.

Stub-column strength of thin-walled square and rectangular hollow sections

Abstract There are several methods for the evaluation of the ultimate load of compressed rectangular thin-walled hollow stub-columns. The aim of the present paper is to review some of these and to compare their results with experimental results obtained from tests on a series of specimens. Conclusions are drawn on the validity and on the range of practical application of these methods.

Beam-column welded stud connections☆

Stud shear connectors have been widely used for many years for providing the composite connection between steel and concrete in composite construction. The present paper is concerned with the feasibility of a similar technique for framing connections between beams and columns by means of threaded connectors. The new kind of connection would be especially suitable for hollow section columns because existing types of connections generally create problems. Several stud sections and diameters have been investigated and tests carried out: tensile and shear tests on welded studs and simple connection specimens and tests on beam to column assemblages. On the basis of the experiental results, a design method is suggested, which is in appearance quite similar to that used for bolted connections.

Guidelines for the design of braced frames with semi-rigid connections

Abstract This paper describes the mode of application of the two usual design philosophies-elastic and plastic-to braced frames with semi-rigid connections. The attention of the designer is particularly drawn to the influence of the second-order effects on the frame stability. Practical recommendations that allow one to define the collapse load of the frame in the most convenient way are proposed. Examples illustrate the design principles stated.

BUCKLING OF UNSTIFFENED COMPRESSION CURVED PLATES

Abstract Motivated by a specific example of a box arch of a bowstring bridge under erection in Belgium, a parametric study of the non-linear behaviour of curved plates under circumferential compression has been undertaken. The influence of the geometrical parameters, radius of curvature R and slenderness b/t, has been investigated by means of a finite element program and results are presented in the form of behavioural curves. Finally a general design formula for curved plates derived from parametric calculations is proposed for specific ranges of R and b/t that cover the main field of civil engineering structures.

Simulation of the behaviour of stiffened box girders with and without shear lag

Abstract A finite element program with large deformations and plasticity is used to analyse the behaviour of stiffened compression flanges of box girders. Simulations are performed for pure bending and for bending with shear in order to investigate the diminishing of the shear lag effect at collapse. It is concluded that at the actual ultimate load, shear lag has largely disappeared but that a design at ultimate load without consideration of the shear lag may entail an inelastic behaviour under service load. First yielding occurs in the centre of the stiffened panel for pure bending and in the middle of the unloaded edges when elastic shear lag becomes important. A substantial increase of the ultimate load can be expected from an increase of the stiffener rigidity.

Contribution to the design of sway composite frames

This paper presents numerical and analytical studies carried out at Liège University, as part of a European research project, with the objective to investigate the in-plane behaviour of composite sway frames under static loading.

Load-Introdcution resistance of column webs in strong axis beam-to-column joints

Present paper is aimed at presenting the results of the study performed at the University of Liege on the deformability and the resistance of column web panels in strong axis beam-to-column joints, when subjected to transverse loads carried over by the beam(s).