Steel Building Construction Research Articles

Pull-out failure capacities of cold-formed steel batten screw connections at sub-zero temperatures

Cold-formed steel (CFS) roof and wall cladding systems are used worldwide, and are constructed using high-strength, thin steel battens and claddings. In North American countries, which are frequently subjected to blizzards (winter storms), these cladding systems are particularly vulnerable to pull-out failures during combined windstorm and snowy conditions. Despite extensive research studies investigating the pull-out failure mechanism and the critical parameters of screw connections between cladding and battens at ambient temperature, the behaviour of these connections under blizzard conditions has not been experimentally investigated. To fill this knowledge gap, an experimental study was undertaken that included 144 laboratory tests of screw connections in battens of varying grades and thicknesses, and three distinct types of screws. The pull-out failure capacities of screw connections in battens were evaluated under wind suction loading at four different temperatures, including ambient and sub-zero temperatures. The results of the study provided insights into the pull-out failure mechanisms of screw connections in battens and enabled the development of suitable design rules for combined wind action and sub-zero temperature conditions. The findings of this study are expected to be of significant value to engineers and building designers who are involved in the construction of lightweight cold-formed steel buildings.

Electroslag Welding Applications for Steel Building Construction in Japan: A State-of-the-Art Review

Electroslag welding (ESW) is advantageous for the improvement of the efficiency of welding thick steel plates, and the application of ESW has been gradually spreading to civil structures such as steel bridges and steel building structures. This paper presents a review of state-of-the-art ESW application for steel building structures in Japan. A brief history of the development of ESW technology, which involves the installation of interior diaphragm plates in welded built-up box columns for high-rise steel buildings, is first introduced, followed by a recent recommendation for the design and fabrication of ESW joints to prevent brittle fracture under earthquake loading.

Revolutionizing steel building project cost overrun risk assessment by Bayesian network

PurposeIn recent years, cost overrun becomes a common problem in steel building construction projects. The average percentage can vary widely depending on the project type, size, complexity and location. The steel structure change ratio in Taiwan is from 1 to 18% in statistics. The contractors always put every possible effort into preventing or mitigating project cost overruns, and one of the approaches is an accurate cost overrun risk estimate. Traditional project cost overrun risk assessment models mainly focus on macro-level evaluation and may not function well for the project-specific level (micro-level). This study creates a network-like connection model between the outcome (i.e. cost overrun risk) and the associated root causes in which the project status evaluation checklists of design, manufacturing, construction and interfaces are used to evaluate the checklists' influences through the Bayesian network (BN) composed by intermediate causes.Design/methodology/approachDue to the constraint of data availability, BN nodes, relationships and conditional probabilities are defined to establish a BN-based steel building project cost overrun assessment model following the knowledge of experts. Because of the complexity of the BN, the construction of the BN structure is first to build BN's fault tree (FT) hierarchy. And then, basic BN framework is constructed by the transformation of the FT hierarchy. Furthermore, some worthwhile additional arcs among BN nodes are inserted if necessary. Furthermore, conditional probability tables (CPTs) among BN nodes are explored by experts following the concept of the ranked node. Finally, the BN-based model was validated against the final cost analysis reports of 15 steel building projects done in Taiwan and both were highly consistent. The overall BN-based model construction process consists of three steps: (1) FT construction and BN framework transformation, (2) CPT computation and (3) model validation.FindingsThis study established a network-like bridge model between the outcome (i.e. cost overrun risk) and the root causes in a network of which cost influences are evaluated through the project-specific status evaluation checklists of design, manufacturing, construction and interfaces. This study overcame several limitations of the previous cost overrun risk assessment models: (1) few past research support assessment of cost overrun based on real-time project-owned data and (2) the traditional causal models inadequately depict interdependencies among influence factors of cost overrun at the network. The main influence factors of the cost overrun risk at the steel building projects in Taiwan were also examined using sensitivity analysis. The main root causes of cost overrun in steel building projects are design management and interface integration.Originality/valueThe proposed model belongs to the project-specific causal assessment model using real-time project-owned status checklist data as input. Such a model was seldom surveyed in the past due to the complicated interdependence among causes in the network. For practical use, a convenient and simple regression equation was also developed to forecast the cost overrun risk of the steel building project based on the root causes as input. Based on the analysis of cost overrun risk and significant influence factors, proper tailor-made preventive strategies are established to reduce the occurrence of cost overrun at the project.

A PROPOSAL FOR SEISMIC VULNERABILITY ASSESSMENT OF PRE-ENGINEERED STEEL BUILDINGS IN BANGLADESH USING SIMPLIFIED JAPANESE INDEX METHOD

At present seismic evaluation of structures has become very crucial in Bangladesh as the country is in earthquake prone region. Lots of studies have been performed and many methods have been proposed for the rapid seismic evaluation of reinforced concrete (RC) buildings. Over the past two decades the country has been going through an important evolution which is rapid construction of pre-engineered steel buildings (PEB). Unfortunately, there has not been a single research work done or any method proposed for the seismic evaluation of these type of structures. In this work, simplified structural evaluation which is based on Japanese Index Method has been used for the seismic evaluation of 05 existing PEB steel structure. The structural seismic index of the building, IBS has been compared with the seismic judgement index IBSO which is a function of seismic zone co-efficient, structural importance coefficient and normalized acceleration response spectrum. The service load index IBD has also been compared with service load judgement indices, IBD01 and IBD02 which has been calculated from the material strength. For example, from the judgement of one building at ground floor, 0.5IBSO ≦ IBS＜IBSO and IBD02＜IBDhave been observed hence immediate detail evaluation recommended.

Comparative analysis of unbraced and chevron braced steel buildings of different storeys

With the new construction requirements and practices, construction of steel buildings is increasing rapidly especially in earthquake prone zones. A steel structure can be considered as unbraced if the structural elements itself provide the lateral stability and a braced structure is the one where the braced frames provide the lateral stability. Chevron bracing, also known as inverted V-bracing is one of the types of Concentrically Braced Frames. Linear static and dynamic analysis are carried out to study the behaviour of G + 3, G + 7 and G + 10 storied steel buildings with and without chevron bracings using STAADPro. The steel structure is assumed to be situated in Chennai and is designed as a commercial building for the effect of wind and seismic load. The steel structure is designed as moment resisting framed structure with and without bracings. The response of the various configurations of the steel structure is compared based on the base shear, peak storey shear, inter- storey drift, spectral acceleration, time period and frequency.

Analysis of Steel Buildings with Steel Plate Shear Walls at the Corners with Varying Thickness

Nowadays the construction of steel buildings is very common. When a building's height increases, its stability is taken into account. Shear walls have to be added to these structures for them to endure the lateral loads caused by wind and seismic activity. Steel plate shear walls (SPSW), one of the shear wall types, are the most efficient since they are lighter and thinner, enhancing the architectural space and rigidity of the structures. This study employs ETABS software to display the seismic analysis of a 15-story steel structure in seismic zone III that has steel plate shear walls at the corners and centre. This article also compares the performance of another 15-story steel building with steel plate shear walls of different thicknesses (15mm, 20mm, and 25mm). The steel building with the thicker steel plate shear walls at the corners performs better in terms of storey displacement and storey drift when compared to other structures. According to IS 1893:2016, the models are examined using the response spectrum method.

ANALYSIS OF THE INFLUENCE OF BACKHAND AND FOREHAND WELDING DIRECTIONS ON MECHANICAL PROPERTIES USING THE SMAW METHOD

Abstract
 The use of metal materials to support human life continues to grow along with the rapid development of science and technology. This greatly influences the technology to process it into a ready-to-use product. Among the production techniques used to make a product is the welding process. Welding is a method of joining that is widely used in steel building construction and machine construction. Another connection method used on metal joints is bolts and rivets. Welding technology, besides being able to be used to join and cut metal, can also be used to fill holes in castings, make hard coatings on tools, thicken worn parts, and other kinds of repairs.
 AISI 1037 is a carbon steel with a carbon content of around 0.37%, which is classified as Medium Carbon Steel. The tensile strength of AISI 1037 is 650 MPa with a yield stress of 350 MPa. A test has been carried out on AISI 1037 with the welding method, where the welding method used is the 1G and 1 F welding process. With this method compared to the mechanical properties of the welding results, the seam used is seam V with an E 6013 electrode with a diameter of 2.6mm. The welding process refers to the AWS D1.1 standard with the SMAW welding type with a plate thickness of 5mm.

PEMANFAATAN BUILDING INFORMATION MODELLING (BIM) PADA PERANCANGAN STRUKTUR BAJA TERHADAP BEBAN GEMPA

This study focuses on designing the steel structure construction toward earthquake load, which uses Istana Qur’an as a research object. Modeling and designing the steel structural building by using two different software, SAP2000, and Tekla Structure. In the making process, the authors made presumptions on workload according to Indonesian Design Standards such as minimum design loads, seismic load design, seismic load for steel structure design, and joints in steel structure. Not only from a structural strength view for human safety but also the construction time and material cost are also able to be estimated which is becoming faster and more affordable compared to implementing the conventional method. As a full analysis result, in this steel design, there are six different steel profiles were used for steel building construction. For instance, IWF 440.300.11.18 as the column, IWF 350.175.7.11 and IWF 250.125.6.9 as the beams, IWF 200.100.5,5.8 as the gable roof frame, UNP 150.75.9.12,5 as purlin and L 150.150.15 as collar tie.

A state of art review on analysis and design of pre-engineered buildings

Construction of steel buildings is increasing very rapidly due to its strength, flexibility, recyclable nature, longer span, no limitation in size of components and more seismic resistance capacity as compared to concrete buildings. A Pre-Engineered Building (PEB) refers to a building which is engineered at a factory as per the specifications, codes and the loads that will be acting on the structure before production of the building components and then finally assembled at site thereby reducing the completion time. The concept of PEB involves predesigning and prefabrication process. The material usage in PEB is optimized by matching the frame geometry with the bending moment diagram’s shape, which reduces the overall weight of the structure. In the present study, a review on the analysis and design of PEB structure is presented. The study discusses the various components of the PEB system and provides a detailed step to model PEB structures. From the past studies, it has been found that PEB structures are up to 50% lighter due to the usage of tapered I-sections and cold formed “Z” & “C” sections, approximately 35% cheaper as compared to the conventional steel structures and show reduced lateral and vertical displacements when subjected to the seismic loading and can be constructed in half the time taken for conventional steel buildings (CSB). PEB gives a better output from the architectural point of view with large clear spans & flexibility in future expansion. It has also been found that construction of PEB is more sustainable, environment friendly and economical than CSB.11Corresponding Author. E-mail address: sandeepsatheresearch@gmail.com (Sandeep Sathe).

Procjena krivulje oštetljivosti čelične okvirne konstrukcije kod različitih potresa

The aim of this study is to investigate the effect of two categories of earthquake events on the fragility curves of steel building construction (structures with different number of stories) by considering relative lateral displacement as a damage criterion. The categories used to describe the change in the relative lateral position were chosen to be slight, moderate, extensive, and complete. Increased seismic demand increases the probability of exceeding. In other words, the greater the maximum earthquake acceleration, the higher is the probability of exceeding (PoE). In a 3-story structure, the increase in PGA increases the PoE of the structure at extensive failure levels. The fragility curves for the 2nd category earthquakes show a shift from the sleeping mode (gradual increase) to the standing state (rapid increase) compared to the 1st-class earthquakes in the 5-story model. Increasing the number of stories increases the PoE of extensive and large failures. The PoE of the extensive mode in the 7-story model was 10 and 15.5 % higher than that in the 5- and 3-story models, respectively. However, for the complete damage state, the PoE in the 5-story model was 6 and 7 % more than that in the 7- and 3-story models, respectively. Therefore, it can be concluded that increasing the number of stories increases the PoE, but this increase is more evident for the extensive failure level.

Seismic Analysis of Steel Building with Bracing

Abstract: As we know that construction of steel buildings is popular nowadays. To protect buildings from earthquake by providing bracings are very common. Bracing help to resist the lateral load during earthquake. Bracings are providing in structure at various configuration. This paper illustrates the effect of new bracing configuration with existing x bracing configuration. The seismic analysis of the structure has been carried out using ETABS Software.

Fire tests of cold-formed steel walls made of hollow section studs

Light gauge steel frame (LSF) walls as primary load-bearing components have been increasingly used in the construction of cold-formed steel (CFS) buildings. Their fire safety has thus become an important consideration for designers. Currently, LSF walls made of lipped channel section (LCS) studs are commonly used in low-rise buildings, but with the expansion of CFS applications to mid-rise buildings, cold-formed steel square and rectangular hollow section (SHS/RHS) studs are being used to meet the higher load capacity demands. However, the fire resistance of LSF walls made of SHS/RHS studs has not been investigated yet, so their fire resistance levels (FRLs) are unknown, restricting their use in mid-rise buildings. Four full-scale load-bearing standard fire tests were therefore conducted to investigate the performance of cold-formed steel SHS/RHS stud walls exposed to fire. The test results showed that CFS SHS/RHS stud walls achieved a higher FRL due to the superior elevated temperature mechanical properties of CFS SHS/RHS, while the temperature development exhibited good similarity with uninsulated LCS stud walls of the same wall configuration. However, a different thermal behaviour was observed when SHS/RHS studs were used in cavity insulated walls, as the hollow cavity reduced the temperature difference between the stud hot and cold flanges. This eliminated the fire resistance reduction caused by thermal bowing deformations and provided an improved fire performance than cavity insulated LCS stud walls. This paper presents the details of the fire tests and the results.

Selecting suitable procurement system for steel building construction

PurposeThe purpose of this paper is to select a suitable procurement method for steel building construction in Sri Lanka following a systematic method which weigh, both procurement selection factors and existing procurement systems.Design/methodology/approachAn abductive research stance is followed in this empirical study. Procurement selection factors were selected through a critical literature review which was followed by a quantitative questionnaire survey. The collected data were analysed using descriptive statistical analysis and relative important index.FindingsThe critical literature review outlined 46 procurement selection factors, out of which 26 factors were very important in steel building procurement selection. Short construction period and higher constructability of design are ranked at the top with the highest priority rating factors. Management-oriented procurement system was selected as the most appropriate procurement system for steel building constructions within the Sri Lankan context.Research limitations/implicationsThe study is limited to widely use three procurement systems in Sri Lankan construction industry. Yet, the process followed in selecting the most appropriate procurement system could be applied for other contexts. The implications of the study are mainly identifying management-oriented procurement as the most suitable procurement method for steel building construction in Sri Lanka.Practical implicationsThe systematic procedure of procurement method selection for steel building construction may use in the Sri Lankan construction industry to limit the resource loss due to wrong selection of procurement.Originality/valueA study which critically and comprehensively presenting a procurement selection process for steel building construction is not recorded in Sri Lanka prior to this study.

Tightening a Tension-Control Bolt without a Tension-Control Gun

AbstractTension control (TC) bolts are the most-used bolt in steel building construction. They are designed to be tightened using a TC gun. It is not unusual to find places where the TC gun will no...

Optimum Design of Cold‐formed Steel Beams: Particle Swarm Optimisation and Numerical Analysis

ABSTRACTCold‐formed steel (CFS) members, when subjected to optimisation, can significantly increase their ultimate load carrying capacity leading to a more economical and efficient structural system. This paper presents the details of an investigation on optimisation of CFS beams subjected to bending capacity and an investigation of shear and web crippling capacities of optimised sections. The optimisation was aimed to meet construction constraints reported in Eurocode 3 (EC3). In this research, 4 different CFS sections were considered including the introduction of 2 novel sections (Super Sigma and Smart Beam) which has closer shear center to the web and less susceptible to web buckling. The bending capacity of the available sections were obtained based on the effective width method reported in EC3, while the optimisation procedure was performed using particle swarm optimisation (PSO). The capacities of the optimised CFS beams were also obtained using the nonlinear finite element (FE) analysis and the FE results were compared with EC3. The FE results showed that the Smart beam and Super Sigma claim dual advantage of increase in section moment capacity and restrain against torsional effect than the conventional CFS channel sections with the same amount of material. These optimised cold formed steel beams can be employed in light gauge steel building constructions.

THE BASICS OF FIXED CONNECTION IN ANALYSIS AND DESIGN OF STEEL FRAMES

This paper is concerned with the out-of-date design criteria in the assumption of end boundary conditions in computer analysis and design of steel building frames in some sectors of heavy industry. The two major concerns are addressed: one is the use of pinned end for the steel column base plates whose details are fixed end, and the second is the use of pinned connection design of steel beam to steel column in lieu of using moment connection. A typical frame is shown for demonstration purposes. The typical connection details used are shown. The author presents the pinned and fixed connection definition with reference to AISC Specification for Structural Steel Buildings. Examples of actual pinned end and actual fixed end are shown with reference to actual structures. A simple structure of a single column traffic sign post with a cantilever beam at the top of the column was selected to demonstrate a fixed end column base and a beam to column moment connection. It is the aim of this paper to clarify this simple but significant concept of fixed connections of column base plates and moment connection of beam to column, which in turn will lead to significant savings in the construction of steel buildings.

IMPACT OF INTRODUCING SEMI-RIGID MOMENT FRAMES ON SEISMIC RESPONSE OF BRACED FRAMES

Maximum seismic inelastic drift demand in a steel building with braced frames as primary seismic-force-resisting (SFR) system tends to concentrate in few stories without considering inherent participation of designed gravity-force-resisting (GFR) system in actual structural stiffness and strength. The influence of GFR system on stiffness and strength can be taken into account by considering the composite action in beam-to-column shear connections that exist in modern steel building construction to form actual semi-rigid moment-resisting frames. Therefore, modeling semi-rigid moment frames as an equivalent to the GFR system in braced frame buildings could be utilized as a representative to the strength provided by gravity frames. This paper presents a seismic evaluation of a six-story chevron braced frame, with and without semi-rigid moment frame. Four different cases are investigated under a set of ground motions and results are discussed in terms of story drift distribution along the height. The results pointed out that the current findings lay a foundation to conduct further investigation on the seismic performance of braced frames as designed SFR system together with GFR system.

AMASS: ADVANCED MANUFACTURING FOR THE ASSEMBLY OF STRUCTURAL STEEL

This paper describes a collaborative project between the US, Ireland, and Northern Ireland (UK) to investigate advanced manufacturing cutting techniques for the creation of a new class of intermeshed steel connections that rely on neither welding nor bolting. To date, advanced manufacturing equipment has only been used to accelerate traditional processes for cutting sheet metal or other conventional fabrication activities. Such approaches have not capitalized on the equipment's full potential. This project lays the groundwork to transform the steel building construction industry by investigating the underlying science and engineering precepts for intermeshed connections created from precise, volumetric cutting. The proposed system enhances the integration between design, fabrication, installation and maintenance through building information modeling platforms to implement advanced connections. Fully automated, precise, volumetric cutting of open steel sections introduces intellectual challenges regarding the load-transfer mechanisms and failure modes for intermeshed connections. The research activity addresses knowledge gaps concerning the load resistance and design of steel systems with intermeshed connections. Physical tests, finite element simulation and multi-scale modeling are being used to investigate the mechanics of intermeshed connections including stress and strain concentrations, fracture potential and failure modes, and to optimize connection geometry.

Improved Calculation Method for Insulation-based Fire Resistance of Composite Slabs

Abstract Floor slabs play a critical role in the fire resistance of buildings, not only by maintaining structural stability and integrity, but also by providing thermal insulation to limit the rise in temperature of floors above a fire. Composite slabs, consisting of concrete topping on steel decking, are common in steel building construction, but the profiled geometry of the decking makes the analysis of heat transfer in composite slabs more complex than for flat slabs. A method for calculating the insulation-based fire resistance of composite slabs with profiled steel decking is provided in Annex D of Eurocode 4 (EC4). However, the applicability of the EC4 calculation method is limited to a range of commonly used slab geometries from the 1990s, which is narrower than the range used in current practice. In addition, the EC4 calculation method assumes a specific value of moisture content for the concrete, and different values of moisture content can significantly affect the fire resistance, as shown in this study. This paper proposes an improved algebraic expression for estimation of the insulation-based fire resistance of composite slabs that explicitly accounts for moisture content and is applicable to an extended range of slab geometries. The proposed expression is developed based on computed values of fire resistance obtained from a validated finite element modeling approach. A set of 54 composite slab configurations are selected for analysis using a sequential experimental design. The accuracy of the proposed method is verified against numerical results for an additional set of 32 slab configurations and is also validated against experimental data. Comparisons of the proposed calculation method with the results of the verification analyses show deviations of less than 15 min in all cases for the insulation-based fire resistance of the composite slabs.

Improved calculation method for insulation-based fire resistance of composite slabs

Floor slabs play a critical role in the fire resistance of buildings, not only by maintaining structural stability and integrity, but also by providing thermal insulation to limit the rise in temperature of floors above a fire. Composite slabs, consisting of concrete topping on steel decking, are common in steel building construction, but the profiled geometry of the decking makes the analysis of heat transfer in composite slabs more complex than for flat slabs. A method for calculating the insulation-based fire resistance of composite slabs with profiled steel decking is provided in Annex D of Eurocode 4 (EC4). However, the applicability of the EC4 calculation method is limited to a range of commonly used slab geometries from the 1990s, which is narrower than the range used in current practice. In addition, the EC4 calculation method assumes a specific value of moisture content for the concrete, and different values of moisture content can significantly affect the fire resistance, as shown in this study. This paper proposes an improved algebraic expression for estimation of the insulation-based fire resistance of composite slabs that explicitly accounts for moisture content and is applicable to an extended range of slab geometries. The proposed expression is developed based on computed values of fire resistance obtained from a validated finite element modeling approach. A set of 54 composite slab configurations are selected for analysis using a sequential experimental design. The accuracy of the proposed method is verified against numerical results for an additional set of 32 slab configurations and is also validated against experimental data. Comparisons of the proposed calculation method with the results of the verification analyses show deviations of less than 15 min in all cases for the insulation-based fire resistance of the composite slabs.