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Article
Publication date: 7 September 2023

Nor Salwani Hashim, Fatimah De’nan and Nurfarhah Naaim

Nowadays, residential buildings have become increasingly important due to the growing communities. The purpose of this study is to investigate the behavior of a steel structural…

Abstract

Purpose

Nowadays, residential buildings have become increasingly important due to the growing communities. The purpose of this study is to investigate the behavior of a steel structural framing system that incorporates lightweight load-bearing walls and slabs, and to compare the weight of materials used in cold-formed and hot-finished steel structural systems for affordable housing.

Design/methodology/approach

Four types of models consisting of 243 members were simulated. Model 1 is a cold-formed steel structural framing system, while Model 2 is a hot-finished steel structural framing system. Both Models 1 and 2 use lightweight wall panels and lightweight composite slabs. Models 3 and 4 are made with brick walls and precast reinforced concrete systems, respectively. These structures use different wall and slab materials, namely, brick walls and precast reinforced concrete. The analysis includes bending behavior, buckling resistance, shear resistance and torsional rotation analysis.

Findings

This study found that using thinner steel sections can increase the deflection value. Meanwhile, increasing member length and the ratio of slenderness will decrease buckling resistance. As the applied load increases, buckling deformation also increases. Furthermore, decreasing shear area causes a reduction in shear resistance. Thicker sections and the use of lightweight materials can decrease the torsional rotation value.

Originality/value

The weight comparison of the steel structures shows that Model 1, which is a cold-formed steel structure with lightweight wall panels and lightweight composite slabs, is the most suitable model due to its lightweight and affordability for housing. This model can also be used as a reference for the optimal design of modular structural framing using cold-formed steel materials in the field of civil engineering and as a promotional tool.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 27 July 2023

Li Fan and Biao Nie

This paper aims to investigate the evolution law of surface characteristic of corroded cold-formed thin-walled steel in industrial environments.

Abstract

Purpose

This paper aims to investigate the evolution law of surface characteristic of corroded cold-formed thin-walled steel in industrial environments.

Design/methodology/approach

Five test specimens sourced from cold-formed thin-walled C-shaped steel that have been in service for three years in actual industrial environments were subjected to surface characteristic test. The surface characteristic of corroded hot-rolled steel and cold-formed steel were compared and analyzed. The relationship between the surface morphology parameters and the average corrosion depth was established.

Findings

The evolution law of the surface morphology of corroded cold-formed thin-walled steel and corroded hot-rolled steel was similar. The frequency histogram of corrosion depth was mainly single peak with high values on the middle and low values on both sides. The corrosion depth conformed to the normal distribution. The roughness average height and the root mean square of surface height gradually increased linearly with increasing the average corrosion depth.

Originality/value

The reduction in the standard deviation of corrosion depth, the maximum corrosion depth, the roughness average height and the root mean square of surface height of the cold-formed thin-walled steel was smaller than those of the hot-rolled steel.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 28 June 2021

Flávio Arrais, Nuno Lopes and Paulo Vila Real

Sigma cross-section profiles are often chosen for their lightness and ability to support large spans, offering a favourable bending resistance. However, they are more susceptible…

Abstract

Purpose

Sigma cross-section profiles are often chosen for their lightness and ability to support large spans, offering a favourable bending resistance. However, they are more susceptible to local, distortional and lateral-torsional buckling, as possible failure modes when compared to common I-sections and hollow cross-sections. However, the instability phenomena associated to these members are not completely understood in fire situation. Therefore, the purpose of this study is to analyse the behaviour of beams composed of cold-formed sigma sections at elevated temperatures.

Design/methodology/approach

This study presents a numerical analysis, using advanced methods by applying the finite element software SAFIR. A numerical analysis of the behaviour of simply supported cold-formed sigma beams in the case of fire is presented considering different cross-section slenderness values, elevated temperatures, steel grades and bending moment diagrams. Comparisons are made between the obtained numerically ultimate bending capacities and the design bending resistances from Eurocode 3 Part 1–2 rules and its respective French National Annex (FN Annex).

Findings

The current design expressions revealed to be over conservative when compared with the obtained numerical results. It was possible to observe that the FN Annex is less conservative than the general prescriptions, the first having a better agreement with the numerical results.

Originality/value

Following the previous comparisons, new fire design formulae are analysed. This new methodology, which introduces minimum changes in the existing formulae, provides at the same time safety and accuracy when compared to the numerical results, considering the occurrence of local, distortional and lateral-torsional buckling phenomena in these members at elevated temperatures.

Details

Journal of Structural Fire Engineering, vol. 12 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 21 August 2020

Mohammad Adil Dar, N. Subramanian, Manmohan Gupta Baniya, M. Anbarasu, Hermes Carvalho and A.R. Dar

The purpose of this paper is to discuss the performance of efficient cold-formed steel (CFS) sections in building a truss system. A comparative study was performed comparing…

Abstract

Purpose

The purpose of this paper is to discuss the performance of efficient cold-formed steel (CFS) sections in building a truss system. A comparative study was performed comparing trusses built with cold-formed and hot-rolled sections.

Design/methodology/approach

Medium-scale specimens were fabricated and tested under monotonic loading. Closed CFS sections (tubular sections) were adopted as compression members of the truss, against the open sections (angle sections) in the hot-rolled steel truss. While as open sections (angle sections) were adopted as tension members in both these cases, the performance assessment was made on the basis of the peak loads carried by the trusses, the vertical deflections and the failure modes exhibited.

Findings

The results of this study indicated that the overall strength, strength-to-weight ratio and overall convenience in terms of cost and fabrication, in the CFS truss was better than that of the hot-rolled one. Also, the judicious utilization of steel which has limited reserves can be achieved.

Originality/value

Cold-formed and hot-rolled sections are widely used in the steel structures. There are advantages and disadvantages in using each of these configurations, discussed in this work. The advantages are widely known by the scientific community; however, few studies are developed with the purpose of quantifying the gains of each solution. Thus, this work emerges with great innovation, with regard to the experimental evaluation of the trusses' behavior composed of different structural sections.

Details

International Journal of Structural Integrity, vol. 12 no. 6
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 17 October 2017

Hélder Craveiro, João Paulo Correia Rodrigues and Luis Laim

The use of cold-formed steel members has increased significantly in the past few years; however, its design is only briefly addressed in the current design codes, such as the EN…

Abstract

Purpose

The use of cold-formed steel members has increased significantly in the past few years; however, its design is only briefly addressed in the current design codes, such as the EN 1993-1-3. To evaluate the compressive behavior of single and built-up cold-formed steel members, at ambient and simulated fire conditions with restrained thermal elongation, experimental and numerical tests were undertaken.

Design/methodology/approach

Four cross-section shapes were tested, namely, one single (lipped channel), one open built-up (I) and two closed built-up (R and 2R), considering two end support conditions, pinned and fixed. Two test set-ups were specifically developed for these tests. Based on the experimental results finite element models were developed and calibrated to allow future parametric studies.

Findings

This paper showed that increasing the level of restraint to thermal elongation and the initially applied load led to lower critical temperatures. Increasing the level of restraint to thermal elongation, the failure is governed by the generated axial restraining forces, whereas for lower levels of restraint to thermal elongation, the failure is controlled by the temperature increasing.

Originality/value

This paper is a contribution to the knowledge on the behavior of cold-formed steel columns subjected to fire, especially on the ones with a built-up cross-section, where results on thermal restrained ones are still scarce. It presented a set of experimental and numerical results useful for the development of numerical and analytical analysis concerning the development of new simplified calculation methods.

Details

Journal of Structural Fire Engineering, vol. 9 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 12 September 2016

Joao Paulo C. Rodrigues, Luis Laim and Hélder David Craveiro

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Journal of Structural Fire Engineering, vol. 7 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 30 April 2019

Mohammad Javad Kazemi, Shahabeddin Hatami, Abdolreza Zare and Ali Parvaneh

This paper aims to study the lateral behavior of cold-formed steel walls with K-shaped bracing by finite element modeling.

Abstract

Purpose

This paper aims to study the lateral behavior of cold-formed steel walls with K-shaped bracing by finite element modeling.

Design/methodology/approach

The braces which have the same section as those for studs and tracks are connected to the frame by screw connections. By pushover analysis, lateral performance of two frame categories, with different dimensions and bracing arrangements, is examined, and the force-displacement diagram and the ultimate strength of walls are extracted. Probable failure modes during lateral loading including distortional buckling of studs, buckling in braces and failure of connections are simulated in the numerical model, and some strengthening suggestions would be offered to prevent brittle failures and, therefore, to increase the lateral strength of the walls.

Findings

The strengthened walls are examined, and their seismic behavior is compared with the original walls. Finally, a parametric study is carried out to evaluate the effect of factors such as thickness of frame members, frame height and yield tension of members on lateral behavior of the shear walls.

Originality/value

In the present research, lateral strength and failure modes of nine types of cold-formed steel shear walls with different arrangements of K-shaped bracing are examined by non-linear finite element analysis, and a parametric study is carried out to extract the effect of the wall frame characteristics on the lateral behavior. Shear walls are classified into two series.

Details

World Journal of Engineering, vol. 16 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 10 November 2023

Varun Sabu Sam, M.S. Adarsh, Garry Robson Lyngdoh, Garry Wegara K. Marak, N. Anand, Khalifa Al-Jabri and Diana Andrushia

The capability of steel columns to support their design loads is highly affected by the time of exposure and temperature magnitude, which causes deterioration of mechanical…

Abstract

Purpose

The capability of steel columns to support their design loads is highly affected by the time of exposure and temperature magnitude, which causes deterioration of mechanical properties of steel under fire conditions. It is known that structural steel loses strength and stiffness as temperature increases, particularly above 400 °C. The duration of time in which steel is exposed to high temperatures also has an impact on how much strength it loses. The time-dependent response of steel is critical when estimating load carrying capacity of steel columns exposed to fire. Thus, investigating the structural response of cold-formed steel (CFS) columns is gaining more interest due to the nature of such structural elements.

Design/methodology/approach

In this study, experiments were conducted on two CFS configurations: back-to-back (B-B) channel and toe-to-toe (T-T) channel sections. All CFS column specimens were exposed to different temperatures following the standard fire curve and cooled by air or water. A total of 14 tests were conducted to evaluate the capacity of the CFS sections. The axial resistance and yield deformation were noted for both section types at elevated temperatures. The CFS column sections were modelled to simulate the section's behaviour under various temperature exposures using the general-purpose finite element (FE) program ABAQUS. The results from FE modelling agreed well with the experimental results. Ultimate load of experiment and finite element model (FEM) are compared with each other. The difference in percentage and ratio between both are presented.

Findings

The results showed that B-B configuration showed better performance for all the investigated parameters than T-T sections. A noticeable loss in the ultimate strength of 34.5 and 65.6% was observed at 90 min (986℃) for B-B specimens cooled using air and water, respectively. However, the reduction was 29.9 and 46% in the T-T configuration, respectively.

Originality/value

This research paper focusses on assessing the buckling strength of heated CFS sections to analyse the mode of failure of CFS sections with B-B and T-T design configurations under the effect of elevated temperature.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 15 December 2021

Fuminobu Ozaki, Ying Liu and Kai Ye

The purpose of this study is to clarify both tensile and shear strength for self-drilling screws, which are manufactured from high-strength, martensitic-stainless and austenitic…

Abstract

Purpose

The purpose of this study is to clarify both tensile and shear strength for self-drilling screws, which are manufactured from high-strength, martensitic-stainless and austenitic stainless-steel bars, and the load-bearing capacity of single overlapped screwed connections using steel sheets and self-drilling screws at elevated temperatures.

Design/methodology/approach

Tensile/shear loading tests for the self-drilling screw were conducted to obtain basic information on the tensile and shear strengths at elevated temperatures and examine the relationships between both. Shear loading tests for the screwed connections at elevated temperatures were conducted to examine the shear strength and transition of failure modes depending on the test temperature.

Findings

The tensile and shear strengths as well as the reduction factors at the elevated temperature for each steel grade of the self-drilling screw were quantified. Furthermore, either screw shear or sheet bearing failure mode depending on the test temperature was observed for the screwed connection.

Originality/value

The transition of the failure modes for the screwed connection could be explained using the calculation formulae for the shear strengths at elevated temperatures, which were proposed in this study.

Details

Journal of Structural Fire Engineering, vol. 13 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 12 June 2017

Chrysanthos Maraveas, Zacharias Fasoulakis and Konstantinos Daniel Tsavdaridis

This paper aims to present technical aspects of the assessment method and evaluation of fire damaged steel structures. The current work focuses on the behavior of structural…

Abstract

Purpose

This paper aims to present technical aspects of the assessment method and evaluation of fire damaged steel structures. The current work focuses on the behavior of structural normal steel (hot-rolled and cold-formed) and high-strength bolts after exposure to elevated temperatures. Information on stainless steel, cast iron and wrought iron is also presented.

Design/methodology/approach

Because of the complexity of the issue, an elaborate presentation of the mechanical properties influencing factors is followed. Subsequently, a wide range of experimental studies is extensively reviewed in the literature while simplified equations for determining the post-fire mechanical properties are proposed, following appropriate categorization. Moreover, the reinstatement survey is also comprehensively described.

Findings

Useful conclusions are drawn for the safe reuse of the structural elements and connection components. According to the parametric investigation of the aforementioned data, it can be safely concluded that the most common scenario of buildings after fire events, i.e. apart from excessively distorted structures, implies considerable remaining capacity of the structure, highlighting that subsequent demolition should not be the case, especially regarding critical infrastructure and buildings.

Originality/value

The stability of the structure as a whole is addressed, with aim to establish specific guidelines and code provisions for the correct appraisal and rehabilitation of fire damaged structures.

Details

Journal of Structural Fire Engineering, vol. 8 no. 2
Type: Research Article
ISSN: 2040-2317

Keywords

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