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The use of cold-formed steel (CFS) members in structural engineering has been on the increase recently due to a wide range of benefits. The placement of electrical and/or plumbing installations within the floor or wall thickness requires that members are being manufactured with holes along the web, inevitably affecting their resistance. This article aims at providing a useful and comprehensive overview of the existing literature regarding CFS members with web holes. Experimental and numerical research on CFS members with web holes subjected to pure compression, bending, web crippling and shear is outlined and discussed. Although research on these types of members date back to the early 1970s, the greatest progress in the research field of CFS members with web holes was achieved during the past 15 years; hence, mostly the research conducted during this period was addressed. Additionally, design proposals are summarised for each of the aforementioned stress states. A brief description of the main concepts of design presented in four principal design codes, as well as numerical solution methods for predicting global, local, and distortional buckling modes, is also presented, aiming to collect the accessible up-to-date knowledge of CFS members with holes and identify areas that were modestly covered by previous research.

If experimental studies are difficult to conduct, the validation of results obtained using numerical procedures can be achieved through comparative analyses performed by different numerical model codes. In this paper, analysis of a simply supported steel beam subjected to fire is performed using open source software OpenSEES and a commercial software ANSYS Workbench. Both material and geometrical nonlinearities are taken into account. Calculation methodology is adopted according to Eurocode standards EN 1991-1-2 and EN 1993-1-2. Results, in terms of the midpoint displacements in time, are compared and discussed.

Reinforced concrete (RC) structures exhibit complex behaviour when subjected to fire. Severe thermal action evokes changes in the material microstructure and thermal-hydral-mechanical properties, depending on the heating rate, moisture, boundary conditions, geometry and size of the heated member, loading type, chemicalphysical interactions, etc. Extensive experimental material research has led to the development of mathematical models and numerical procedures that could, to a certain degree, capture adequately the behaviour of structures under fire conditions. Advanced modelling guidelines have been proposed in standards, such as Eurocode. Based on these recommendations and previous efforts conducted by other researchers, a numerical model is developed in finite element (FE) software ANSYS. The model incorporates temperature dependent physical, thermal and mechanical properties of constituting materials and conducts nonlinear heat transfer and structural analysis, simulating the response of RC frame structure under standard fire action. Explicit modelling of concrete and steel reinforcement allows monitoring of temperature evolution in both concrete and reinforcement elements, deformations, section forces and stresses and strains in reinforcement bars, providing a broad insight into the structural behaviour at both global and local level. Special consideration is given to the influence of fire scenario on RC frame behaviour.

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