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The purpose of this study is to further investigate the potential benefits brought about by the development of modern technology in the steel construction industry. Specifically, the study focuses on the optimization of tapered members for pre-engineered steel structures, aligning with Eurocode 3 standards. By emphasizing the effectiveness of material utilization in construction, this research aims to enhance the structural performance and safety of buildings. Moreover, it recognizes the pivotal role played by such advancements in promoting economic growth through the reduction of material waste, optimization of cost-efficiency and support for sustainable construction practices.

Structural performance at initial analysis and final analysis of the selected critical frame were carried out using Dlubal RSTAB 8.18. The structural frame stability and sway imperfections were checked based on MS EN1993-1-1:2005 (EC3). To assess the structural stability of the portal frame using MS EN 1993-1-1:2005 (EC3), cross-sectional resistance and member buckling resistance were verified based on Clause 6.2.4 – Compression, Clause 6.2.5 – Bending Moment, Clause 6.2.6 – Shear, Clause 6.2.8 – Bending and Shear, Clause 6.2.9 – Bending and Axial Force and Clause 6.3.4 – General Method for Lateral and Lateral Torsional Buckling of Structural Components.

In this study, the cross sections of the web-tapered rafter and column were classified under Class 4. These involved the consideration of elastic shear resistance and effective area on the critical steel sections. The application of the General Method on the verification of the resistance to lateral and lateral torsional buckling for structural components required the extraction of some parameters using structural analysis software. From the results, there was only 5.90% of mass difference compared with the previous case study.

By classifying the web-tapered cross sections of the rafter and column under Class 4, the study accounts for important factors such as elastic shear resistance and effective area on critical steel sections.

Since the use of advanced finite element analysis (FEA) in the design of steel structures has been increasing its popularity in order to avoid unsafe or highly conservative designs, a solid know-how in computer-aided design (CAD) and engineering (CAE) codes is necessary. Therefore the purpose of this paper is to provide an extensive review of useful guidelines concerning modelling, simulation and result validation for the accurate performance of those analyses.

Such guidelines are obtained from international steel design codes like Eurocode 3 and DNV, publications from experienced CAE engineers and renowned FE software companies like Ansys and Altair. Topics like mesh independence, the effect of the load sequence on the load bearing capacity and steel fracture criteria are underlined.

Since the use of advanced FEA in the design of steel structures is becoming more and more traditional due to the increase of its competitiveness when compared to the use of (very) conservative design rules, a solid know-how in CAD and CAE codes is necessary.

This work will be quite useful for structural steel stress engineers, contributing for a safer use of FEA in research and design.

This work will be quite useful for structural steel stress engineers, contributing for a safer use of FEA in research and design.

Brief introduction on the importance and the need for plastic analysis methods were presented in the beginning section of this review. The plastic method for analysis was considered to be the more advanced method of analysis because of its ability to represent the true behaviour of the steel structures. Then in the following section, a literature analysis has been carried out on the previous investigations done on steel plates, steel beams and steel frames by other authors. The behaviour of them under different types of loading were presented and are under the investigation of innovative new analysis methods.

Structure member connections also have the potential for plastic failure. In this study, the authors have highlighted a few topics to be discussed. The three topics in this study are T-end plate connections to a square hollow section, semi-rigid connections and cold-formed steel storage racks with spine bracings using speed-lock connections. Connection is one of the important parts of a structure that ensures the integrity of the structure. Finally, in this technical paper, the authors introduce some topics related to seismic action. Application of the Theory of Plastic Mechanism Control in seismic design is studied in the beginning. At the end, its in-depth application for moment resisting frames-eccentrically braced frames dual systems is investigated.

When this study involves the design of a plastic structure, the design criteria must involve the ultimate load rather than the yield stress. As the steel behaves in the plastic range, it means the capacity of the steel has reached the ultimate load. Ultimate load design and load factor design are the methods in the range of plastic analysis. After the steel capacity has reached beyond the yield stress, it fulfills the requirement in this method. The plastic analysis method offers a consistent and logical approach to structural analysis. It provides an economical solution in terms of steel weight, as the sections designed using this method are smaller compared with elastic design methods.

The plastic method is the primary approach used in the analysis and design of statically indeterminate frame structures.

The application of servo steel struts enables the active control of the excavation-induced deformation in foundation pits. However, there is currently only one design axial force for each servo steel strut, which requires in-situ axial force adjustments based on the experience of site engineers. The purpose of this study is to develop a method for determining the design axial forces of servo steel struts at different excavation steps.

In this study, a hybrid method for determining the design axial forces of servo steel struts in different excavation steps was established based on the combination of the elastic foundation beam model and nonlinear optimisation.

The hybrid method is capable of providing a better set of design axial forces than the original design method. The lateral wall displacement and bending moment could be better controlled. Ordinary steel struts should be prevented from being set between servo steel struts to avoid axial force losses.

The axial forces of the servo steel struts at different excavation steps should be designed to achieve better deformation control effects. Moreover, a well-designed set of axial forces can also reduce the internal forces of the retaining structure.

The hybrid method enables the determination of the design axial forces of servo steel struts at different excavation steps, which can guide axial force adjustments in practical projects.

Stainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known; however, its better behaviour under elevated temperatures can also be important in buildings design. In spite of the initial cost, stainless-steel application as a structural material has been increasing. Elliptical hollow sections integrate the architectural attributes of the circular hollow sections and the structural advantages of the rectangular hollow sections (RHSs). Hence, the application of stainless-steel material combined with elliptical hollow profiles stands as an interesting design option. The purpose of the paper is to better understand the resistance of stainless-steel-beam columns in case of fire

The research presents a numerical study on the behaviour of stainless-steel members with slender elliptical hollow section (EHS) subjected to axial compression and bending about the strong axis at elevated temperatures. A parametric numerical study is presented here considering with and without out-of-plane buckling different stainless-steel grades, cross-section and member slenderness, bending moment diagrams and elevated temperatures.

The tested design methodologies proved to be inadequate for the EHS members being in some situations too conservative.

The safety and accuracy of Eurocode 3 (EC3) design methodology and of a recent design proposal developed for I-sections and cold-formed RHSs are analysed applying material and geometric non-linear analysis considering imperfections with the finite element software SAFIR.

This work examines the effects of strain rate on the effective yield strength of high-strength steel at elevated temperatures, through tensile coupon tests at various strain rates, to propose appropriate reduction factors considering the strain rate effect.

The stress–strain relationships of 385 N/mm2, 440 N/mm2 and 630 N/mm2-class steel plates at elevated temperatures are examined at three strain rate values (0.3%/min, 3.0%/min and 7.5%/min), and the reduction factors for the effective yield strength at elevated temperatures are evaluated from the results. A differential evolution-based optimization is used to produce the reduction-factor curves.

The strain rate effect enhances with an increase in the standard design value of the yield point. The effective yield strength and standard design value of the yield point exhibit high linearity between 600 and 700 °C. In addition to effectively evaluating the test results, the proposed reduction-factor curves can also help determine the ultimate strength of a steel member at collapse.

The novelty of this study is the quantitative evaluation of the relationship between the standard design value of yield point at ambient temperature and the strain-rate effect at elevated temperatures. It has been observed that the effect of the strain rate at elevated temperatures increases with the increase in the standard design value of the yield point for various steel strength grades.

The purpose of this paper is to analyze a new structural design applied in industrial frames using two type of steels (S275 and fire resistant (FR)) with different mechanical resistance against fire. To do it, the authors have taken into account variables such as intrinsic metallic design, span length, intumescent paint thickness, and fire time exposure, which offers information about new scenarios of design in industry.

The key methodology followed has taken into account a modeling program that uses the following variables: 25 and 35 m of span, 45 and 60 fire exposure times, and seven different intumescent paint thickness. An optimum structural design has been evaluated by discretization of each scenario with the particular type of steel, S275 and FR. The obtained approach could be a good guideline for future designs.

The results and analysis have shown a very good and valid idea of a new structural typology using optimum intumescent paint thickness into the final design of the industrial frame considering that it has two different types of steel. It is in realty a handicap since usually mechanical engineers employ structural steel without paying attention to this new feature.

Cheaper structural designs could be obtained using the two different types of steel considering the proper positioning into the full building.

The validity of design of two types of steel plus intumescent paint in building construction has been shown, and this study will encourage designers to use it, in particular in buildings with high fire risk.

This study aims to analyze and discuss the key design assumptions needed for design of car parks in steel, to highlight the impact that the increased fire loads introduced by modern cars and changes in the fire dynamics have on the design, such as fire spread leading to non-localized fires.

In particular, a reliable fire load density to be used for structural design of car park structures is assessed, based on investigations of the fire loads of modern cars. Based on knowledge of fire load and fire performance of cars, the consequences on the fire safety design of steel structures are presented.

Design recommendation about fire load density and fire protection of common steel profiles are given. Finally, the proposed design is compared with a design practice that has been applied in many instances for car parks constructed with unprotected steel, and recommendations for a reliable design process are provided.

Numerous car park buildings have recently been designed of steel structures without passive or active fire protection. The key assumptions that makes possible such design are local fire scenarios, outdated values of the car fire load and utilization of the ultimate steel strength. This paper identifies the shortcomings of such key assumptions, indicating the need for revisiting the methods and possibly even checking the analyses carried out for some already-built car parks.

The steel construction market has undergone gradual development in the past decades given its profound impacts on environment, economy and society. The purpose of this paper is to facilitate a better understanding of the major drivers and issues behind the market development of the steel construction industries around the world.

A three-step desktop research was conducted to select relevant research outputs published in the past 20 years. The research methodology in conducting these studies and their research trends were analyzed. Then the potential influencing factors for the market development of steel construction were identified through a content analysis of the selected studies.

A total of 59 articles were identified accordingly. These influencing factors were divided into five main themes: contextual, institutional, industrial, project-related and individual factors. In terms of the frequencies of these factors appeared in previous studies, “continuous development of standards, codes, and specifications” and “advance in product and process technology” were the top two driving forces in the market development of steel construction, while “cost issues” was the most frequently reported obstacle.

The study takes an initiative to establish a practical classification framework that can be dedicated to illuminating the critical issues or success factors affecting the development of the steel construction market. This framework can help policymakers, industry practitioners and researchers achieve sustaining success in steel construction in the developed, emerging and inactive markets.

This paper aims to study the influence of the presence of steel and polyolefin (PO) fibers on the mechanical and durability properties of fiber and hybrid fiber-reinforced concrete (FRC and HFRC).

Hooked-end steel fibers having a length of 35 mm were applied at four different fiber content 1.0%, 1.5%, 2.0% and 2.5%, respectively. PO fibers having the length of 45 mm were also replaced with steel fibers at three different fiber content, 0.6%, 0.8% and 1.0%, to provide HFRC. The compressive, indirect tensile and flexural strengths; electrical resistivity; and water absorption were evaluated in this study.

The results showed that the addition of both steel and PO fibers led to improvements in the mechanical properties of FRC and HFRC. However, the replacement of steel fibers with PO fibers led to a slight loss in mechanical properties. Also, it was concluded that the addition of various types of fibers to concrete decreased both the electrical resistivity and water absorption compared with the control sample. Finally, distance-based approach analysis was used to select the most optimal mix designs.

According to this method, the HFRC specimen including 1.2% of steel and 0.8% of PO fibers was the most optimal mix design among all fiber-reinforced mix designs.