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Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

MOST readers will be familiar with the ‘Mirrored Beam’ method of using the Three‐Moment Equation for ‘Built‐in’ beams. The following method is somewhat similar but has the added advantage that it can be applied also to beams whose ends are elastically restrained or have a fixed slope.

This paper is mainly aimed at the structural performance of compound cold-formed galvanised steel beams under fire conditions based on the results of a large programme of experimental tests and numerical simulations. The main objective of this research was to assess the critical temperature and time of the studied beams. Other important goals of this research work were to investigate the influence of the cross-sections (C, lipped-I, R and 2R beams) and, above all, of the axial restraint (0, 0.45, 3, 7.5, 15, 30, ∞ kN/mm) to the thermal elongation of the beam and the rotational restraint at beam supports (0, 15, 80, 150, 300, 1,200 and ∞ kN.m/rad) on the fire resistance of this kind of beams.

This paper still provides details of the simulation methodology for achieving numerical stability and faithful representation of detailed structural behaviour and compares the simulation and experimental results, including beam failure modes, measured beam axial forces and beam mid-span deflections.

Good agreement between Abaqus simulations and experimental observations confirms that the finite element models developed with the Abaqus/standard solver are suitable for predicting the structural fire behaviour of restrained cold-formed steel beams.

The results showed above all that the effect of the stiffness of the surrounding structure seems to decrease with the increasing slenderness of the beams.

The purpose of this paper is to show how to find the regions of dynamic instability of a beam axially loaded and visco‐elastically constrained at its ends by Kelvin‐Voigt translational and rotational units variously arranged according to different configurations, by using the equation of boundary frequencies.

With respect to visco‐elasticity the time variable is present as a parameter so that the above‐mentioned exact approach is exploited to draw three‐dimensional diagrams of the dynamic component of the periodic load and its frequency, varying with time and with the viscosity parameter μ characterizing the restraints.

For not rigidly constrained configurations a peculiar asymptotic tendency is recognizable in both cases.

The study allows for identifying the influence of visco‐elastic restraints in the response of a beam under a dynamic axial load. Dynamic excitation occurs in several fields of mechanics: dynamic loads are encountered in structural systems subjected to seismic action, aircraft structures under the load of a turbulent flow and industrial machines whose components transmit time‐dependant forces.

Visco‐elasticity accounts for possible vibration control solutions planned to improve the dynamic response of the rod; they can consist of layers of visco‐elastic material within the body of the modelled element or local viscous instruments affecting the boundary conditions; the latter is the application this paper focuses on.

With this paper a calculation procedure to get an exact solution for particular static configurations of the beam is followed in order to define the influence of visco‐elastic restraints under a dynamic axial load; the responses are given in terms of boundary frequencies domains and are supposed to be useful to learn the behaviour in time and in dependence of the intrinsic viscosity of the restraints.

Finds the regions of dynamic instability of elastic beams constrained at the ends by means of translational and rotational elastic springs, using the equation of boundary frequencies. Obtains the diagrams showing the regions of instability of the beam, as a function of the dynamic component of the periodic forcing function and its frequency, from that equation in exact form. In this procedure inertial, stiffness and constraint characteristics of the examined system are taken into account. Presents selected applications concerning the analysed problem.

FAILURE of panels under static compression, or for that matter under any loads, involves a vast array of problems ranging from properties of material to initial instability and post‐buckling phenomena as occurring in various types of panels. It is not intended here to do justice to all these aspects of the subject but to select a single—but at the same time very important—topic, develop its analysis as fully as possible, and present the results in a readily applicable form. The structure investigated is the single skin stiffened panel under compression and the mode of failure considered, denoted by flexural cum torsional failure, involves predominantly flexure and torsion of the stringer with a wavelength of greater order of magnitude than stringer height and pitch. By torsional deformation of the stringer we understand a rotation of its undistorted cross‐section about a longitudinal axis R in the plane of the plate, the position of which will be selected later on (see FIG. 1b). The panel may, of course, also fail in a local mode of stringer and plate with a short wave‐length of the order of magnitude of stringer height and pitch, but the analysis of this case is not included here (see, however, Argyris and Dunne). Note that a local mode of deformation of a stringer formed by straight walls is commonly defined as a distortion of the cross‐section in which the longitudinal edges where two adjacent walls meet remain straight (see FIG. 1c).

The equation of motion of a beam on multiple supports, subject to prescribed time‐dependent conservative axial loads, is formulated based on Hamilton’s principle and the assumed mode method. The effects of sinusoidal perturbations in respect of the axial loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies into the standard form of a generalized eigenvalue problem. Instability regions are presented for various combinations of support configuration, average value and amplitude of the sinusoidal perturbations of the axial loads.

MUCH reference is made in the aeronautical field to the flutter problem and the subject is receiving the attention of many persons engaged in research, testing, and design. Many aeronautical engineers are well acquainted with some aspect of the problem, and although only a few are concerned with its several phases it is safe to say that all aeronautical men regard it with some degree of interest. It is fitting, therefore, that although it has been adequately treated by many authors from other points of view, a statement be here made summarizing the flutter problem as one of the aeroplane designer. In order that the exact nature of this problem be appreciated it is first necessary that a few of the fundamentals be reviewed.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics and publications of other similar research bodies as issued

This paper presents the results of an experimental and numerical study to clarify the influence of the surrounding building structure in the fire behaviour of reinforced concrete columns with restrained thermal elongation. The parameters studied were: the longitudinal reinforcement ratio, the slenderness of the column and the stiffness of the surrounding structure to the column in fire. The experimental study was complemented by a numerical study carried out using the finite element program SAFIR. Simplified calculation methods proposed in EN1992-1-2 were also used to evaluate the fire resistance of the tested columns. From the application of the 500°C isotherm method, proposed in EN1992-1-2, it can be noticed that this method led to smaller values of the fire resistance than those obtained in the experimental tests. The tabulated data method A, proposed in EN1992-1-2, proved to be very conservative.