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Buckling should be carefully considered in steel assemblies with members subjected to compressive stresses, such as bracing systems and truss structures, in which angles and built-up steel sections are widely employed. These type of steel members are affected by torsional and flexural-torsional buckling, but the European (EN 1993-1-2) and the American (AISC 360-16) design norms do not explicitly treat these phenomena in fire situation. In this work, improved buckling curves based on the EN 1993-1-2 were extended by exploiting a previous work of the authors. Moreover, new buckling curves of AISC 360-16 were proposed.

The buckling curves provided in the norms and the proposed ones were compared with the results of numerical investigation. Compressed angles, tee and cruciform steel members at elevated temperature were studied. More than 41,000 GMNIA analyses were performed on profiles with different lengths with sections of class 1 to 3, and they were subjected to five uniform temperature distributions (400–800 C) and with three steel grades (S235, S275, S355).

It was observed that the actual buckling curves provide unconservative or overconservative predictions for various range of slenderness of practical interest. The proposed curves allow for safer and more accurate predictions, as confirmed by statistical investigation.

This paper provides new design buckling curves for torsional and flexural-torsional buckling at elevated temperature since there is a lack of studies in the field and the design standards do not appropriately consider these phenomena.

Recently, this steel section has found increasing popularity in residential, industrial and commercial buildings with their high load-carrying capacity due to the nature of high strength to weight ratio properties. However, the rise on the price of steel section should be more emphasized; therefore, the optimization in steel section design is needed to overcome the issue of material cost. As such, tapered steel sections save on material use, while the introduction of web openings allows the placement of mechanical and electrical services, plumbing and also aesthetic design considerations.

The purpose of this study is to investigate the lateral torsional buckling behavior of a tapered steel section with an ellipse-shaped opening by analyzing its structural parameters. To achieve this, the finite element analysis (FEA) of the section is modeled using LUSAS software, which allows for a detailed analysis of the section's behavior under varying loads and conditions. It involves the variation in web opening size, opening layout, opening rotation angle and the tapering ratio. Eigenvalue buckling analysis is adopted to know the parametric effects of each 108 model. The size of opening varies from 0.2 to 0.5 d of the total depth where the opening located. There are three type of layouts applied in this study, which are the layouts A, B and C. There are three types of rotation angles for the ellipse-shaped opening, including the non-rotated vertical opening and two additional types formed by rotating the opening 45 degrees clockwise and counterclockwise around the center-point of the ellipse. A fixed-free boundary condition was applied, resulting in a simulation of a cantilever beam. The models are fixed at one end with a larger depth, and free at the other end with a smaller depth. Loading condition is an application of 10 kN/m uniform distributed load in the direction of gravity along the mid-span of the top flange.

It is observed that the model 82 with Layout A, tapering ratio 0.3, opening size 0.5 d and opening rotated in 45 degree anti-clockwise direction results in the highest structural efficiency among the 108 models. Therefore, the buckling moment of model 82 is 1,013.08 kNm with structural efficiency of 481.26, which shows an increase of 3.17% compared to the controlled model.

The FEA results shows a significant increase in ductility and stiffness of the tapered steel section with elipse shape opening and consequently changes in the behaviour of yield point.

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.

Various designs of corrugated webs include trapezoidal, sinusoidal, triangular and rectangular profiles. The increasing use of curved plates has prompted the creation of I-sections made of steel with a corrugated web design. This study aims to examine the effectiveness of an I-beam steel section that features a perforated-triangular web profile.

In the current study, finite element analysis was conducted on corrugated-perforated steel I-sections using ANSYS software. The study focused on inspecting the design of the perforations, including their shape (circle, square, hexagon, diamond and octagon), size of perforations (80 mm, 100 mm and 120 mm) and layout (the position of web perforation), as well as examining the geometric properties of the section in term of bending, lateral torsional buckling, torsion and shear behavior.

The study revealed that perforations with diamond, circle and hexagon shapes exhibit good performance, whereas the square shape performs poorly. Moreover, the steel section’s performance decreases with an increase in perforation size, regardless of loading conditions. In addition, the shape of the web perforations can also influence its stress distribution. For example, diamond-shaped perforations have been found to perform better than square-shaped perforations in terms of stress distribution and overall performance. This was because of their ability to distribute stress more evenly and provide greater support to the surrounding material. The diagonal alignment of the diamond shape aligns with principal stress directions, allowing for efficient load transfer and reduced stress concentrations. Additionally, diamond-shaped perforations offer a larger effective area, better shear transfer and improved strain redistribution, resulting in enhanced structural integrity and increased load-carrying capacity.

Hence, the presence of lateral-torsional buckling and torsional loading conditions significantly impacts the performance of corrugated-perforated steel I-sections.

This paper aims to compare glued laminated timber and steel beams with respect to structural design, manufacturing and assembly costs and the amount of greenhouse gas emissions.

This paper presents structural design requirements in conformance with EN 1993: Eurocode 5 and Eurocode 3. With the help of these standards, expressions are derived to evaluate the design criteria of the beams. Based on the results of life-cycle analysis, the economic properties and environmental impact of the two types of beam are investigated. In this paper, the effect of beam span on the design values, costs and carbon dioxide emissions is analysed when investigating aspects of the structural design, economy and environmental impact. Different cross-sections are chosen for this purpose.

The study shows that the glued laminated (abbreviated as “glulam”) beams have a smaller tendency to lateral torsional buckling than the steel beams, and that they can be cheaper. From an environmental point of view, glulam beams are the more environmentally friendly option of the two beam materials. Furthermore, glulam beams may have a direct positive effect on the environment, considering the carbon storage capacity of the wood. The disadvantage of glued wood is that larger dimensions are sometimes required.

Wind load and the effect of second-order effects have not been considered when analysing the static design. Only straight beams have been studied. Furthermore, the dynamic design of the beams has not been investigated, and the bearing pressure capacity of the supports has not been analyzed. We have investigated timber beams with a rectangular cross-section, and steel beams of rolled I-sections, known as “HEA profiles”. The cost analysis is based mainly on the manufacturing and assembly costs prevalent on the Swedish market. The only environmental impact investigated has been the emission of greenhouse gases. The design calculations are based on the European standards Eurocode 5 and Eurocode 3.

To achieve sustainability in construction engineering, it is important to study the environmental and economic consequences of the building elements. By combining these two effects with the technical design of buildings made of steel and/or timber, the concept of sustainable development can be achieved in the long run.

The study concerns sustainability of building structures, which is an important of the sustainable development of the society.

The paper contains new information and will be useful to researchers and civil engineers.

In this study, the bending strength, flexural buckling strength and collapse temperature of small steel specimens with rectangular cross-sections were examined by steady and transient state tests with various heating and deformation rates.

The engineering stress and strain relationships for Japan industrial standard (JIS) SN400 B mild steels at elevated temperatures were obtained by coupon tests under three strain rates. A bending test using a simple supported small beam specimen was conducted to examine the effects of the deformation rates on the centre deflection under steady-state conditions and the heating rates under transient state conditions. Flexural buckling tests using the same cross-section specimen as that used in the bending test were conducted under steady-state and transient-state conditions.

It was clarified that the bending strength and collapse temperature are evaluated by the full plastic moment using the effective strength when the strain is equal to 0.01 or 0.02 under fast strain rates (0.03 and 0.07 min^–1). In contrast, the flexural buckling strength and collapse temperature are approximately evaluated by the buckling strength using the 0.002 offset yield strength under a slow strain rate (0.003 min^–1).

Regarding both bending and flexural buckling strengths and collapse temperatures of steel members subjected to fire, the relationships among effects of steel strain rate for coupon test results, heating and deformation rates for the heated steel members were minutely investigated by the steady and transient-state tests at elevated temperatures.

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.

Experimental mid/large scale testing of ship-like stiffened panels in compression is a quite expensive exercise that is not standard. Numerical simulations are preferred instead. Because of being relatively inexpensive (cost and time wise), most authors perform an exhaustive design space exploration arriving at a significant number of runs. This work demonstrates that the buckling response with respect to the nondimensional slenderness ratios may well be fitted with nine runs per stiffener geometry.

Efficient derivation of buckling strength formulas for stiffened panels through the employment of design of experiments (DoE) and response surface methodology (RSM) combined with numerical nonlinear experimentation over the entire range of practical geometries.

The surrogate model developed for T-bar stiffeners predicts accurately enough the ultimate stress in the practical design area, while the surrogate models for angle bars and flat bars demonstrate difference between 10 and 30% from common structural rules (CSR).

To the authors' best knowledge, the statistical-based formal and rigorous approach of DoE and RSM to obtaining buckling surfaces for stiffened panels is performed for the first time. The number of required observations per stiffener type has not been addressed yet as each work selects its own sampling scheme without formal reasoning. This work comes to frame the number of observations for efficient surrogate model building.

This paper aims to present the results of a study on the behaviour of cold-formed galvanized steel beams subjected to fire, using the results of a large programme of experimental tests.

The research investigated the influence of web stiffeners in the sections and the stiffness of the surrounding structure, including the axial and rotational restraining to the thermal elongation, on the flexural behaviour of the beams in case of fire. In other words, the structural response of different open cold-formed steel beams, with and without web stiffeners, was compared in case of fire.

The results showed that a good choice between using cold-formed steel beams, with and without web stiffeners, may depend on the section shape and the internal forces generated in these members during a fire.

Temperatures in the furnace and at several points of the beams, as well as deformations and restraining forces and moments, were measured to achieve those goals and consequently to assess the critical time and temperature of these beams.

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 is given. The bibliography at the end of the paper contains 1,726 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 1996‐1999.