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The behaviour of hot-rolled high-strength steel (HSS) tubular sections under combined compression and uniaxial bending was investigated both experimentally and numerically. The experimental programme encompassed a series of material coupon tests, initial geometric imperfection measurements, residual stress measurements and 12 tests on stub columns subjected to uniaxial eccentric compression. Numerical models were developed and validated against the experimental results. An extensive parametric study was then performed with the aim of generating further structural performance data over a wider range of cross-section slendernesses, aspect ratios and applied eccentricities. The results were utilised for an assessment of the applicability of relevant Eurocode provisions to HSS cross-sections under combined loading. Conclusions regarding the applicability of Eurocode interaction curves to S460 and S690 square and rectangular hollow sections are presented. [ABSTRACT FROM AUTHOR]

Steel and steel-concrete composite construction is employed in a substantial proportion of low-rise and multi-storey buildings. Design codes for these forms of structure have evolved over many years, but are currently essentially founded upon the assumption of elastic-plastic or rigid-plastic material behaviour and largely disregard the beneficial influence of strain hardening. This simplificaton can result in overly conservative predictions of capacity, particularly in the case of stocky, bare steel cross-sections and composite beams under sagging bending moment. The continuous strength method is an alternative deformation-based design approach that allows for strain hardening, provides more accurate predictions of member capacities and, thus, enables more efficient structural solutions to be achieved. In this paper, the development and application of the continuous strength method to steel structures is explained and extension of the method to steel-concrete composite design is outlined. [ABSTRACT FROM AUTHOR]

Prestressed stayed columns offer an innovative and aesthetically attractive solution where designs demand long and slender elements under compression. The addition of cross-arms and pretensioned cables to the columns provides significant lateral and rotational support that can result in a marked increase of the buckling capacity. The current work presents a simplified model, comprising discrete rigid links and springs with a mathematically exact formulation including the destabilising effect of cable slackening, which mimics the response of stayed columns and reveals the governing physical parameters that drive the behaviour. A recent finite-element study had indicated that these structural components are likely to exhibit interactive buckling phenomena, particularly if the critical buckling mode is antisymmetric, leading to highly unstable responses. However, by its very nature, that study could not reveal the bifurcational structure of the equilibrium response. The results from the present model reveal similar behaviour to that observed in the earlier finite-element study. A sequence of bifurcations is found that switch the post-buckling response from one mode to another by way of a path of interactive buckling. [ABSTRACT FROM AUTHOR]

Under significant seismic loading conditions, the response of concentrically braced frames largely depends on the behaviour of the diagonal braces, which represent the key energy dissipating zones. Although the hysteretic response of steel braces under cyclic axial loading has been examined in previous studies, there is a need for further assessments that focus on quantifying failure. This paper describes the development of detailed finite-element models of hollow sections subjected to cyclic axial loading. The effects of initial imperfections and cyclic hardening are taken into consideration and the models are validated against data from 19 tests. A method to predict the fracture life of bracing members under cyclic loading is also described. Using the numerical models, parametric studies are undertaken to assess the influence of global and local slendernesses on the performance of the braces - both are found to affect the occurrence and severity of local buckling under cyclic loading, which causes high localised strains at the corner areas of sections, leading to fatigue fracture. A predictive equation addressing the coexisting influence of global slenderness and local slenderness on displacement ductility is presented. The observations in the current study are compared with conclusions from other experimental programmes, and the discrepancy between the findings is discussed. [ABSTRACT FROM AUTHOR]

Following the introduction of hot-finished elliptical hollow sections to the construction industry, recent research has been performed to develop supporting structural design guidance. This paper focuses on shear resistance. Twenty-four shear tests were performed on hot-finished steel elliptical hollow section members. The shear tests were arranged in a three-point bending configuration with span-to-depth ratios ranging from 1 to 8. This enabled the study of cross-section resistance in shear and the interaction between shear and bending. Measurements were taken of cross-section geometry, local initial geometric imperfections and material properties in tension. Test results, including moment--rotation histories, are presented. Additional results were generated numerically. These results have been used to verify proposed design expressions for shear resistance and resistance to combined shear and bending. Further investigations into design criteria for shear buckling are currently under way. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the life-cycle costs of aluminium alloy and stainless steel and compares them to ordinary structural carbon steel. The study’s results show that on an initial cost basis, carbon steel offers the most competitive solution. However, with additional life-cycle costs including maintenance, end-of-life costs and the residual value of the structure, aluminium alloy and stainless steel offer more competitive solutions.

The initial material cost of structural stainless steel is about four times that of structural carbon steel, largely owing to the expense of the alloying elements and the relatively low volume of production. Given broadly similar structural performance, additional areas of benefit need to be identified and exploited in order to establish stainless steel as a viable alternative material for construction. In addition to the familiar benefits of corrosion resistance, low maintenance, high residual value and aesthetics, one such area is fire resistance. Stainless steel generally displays superior strength and stiffness retention at elevated temperature when compared to carbon steel, but also exhibits greater thermal expansion. The current paper describes experimental, numerical and analytical investigations into the elevated temperature response of stainless steel structures. Comparisons are made with the behaviour of carbon steel structures in fire and proposals for improved structural fire resistant design guidance for stainless steel are described. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including buckling behaviour of cold-formed steel, influence of strain-hardening on structural response and steel capacity, and a numerical study of steel response under compression and bending.

An introduction is presented in which the editor discusses various reports within the issue on topics including the behavior of Hennebique reinforced concrete structural systems, chloride penetration, and behavior of concrete structures subjected to extreme loading.

An introduction is presented in which the editor discusses various reports within the issue on topics including assessing and enhancing ductility in nonseismically designed reinforced concrete buildings and the influence of frictional sliding fuses on the ductility of low-rise structure.

An introduction is presented in which the editor discusses various reports within the issue on topics including steel sheet pile wall design, the development of a stress-strain model for rectangular concrete column and novel composite floor system.