Steel Sections Research Articles (Page 4)

IntroductionWith the large-scale construction of high-rise and super high-rise buildings, structures combining ultra-high strength concrete and steel sections are increasingly applied in practical engineering.MethodsAccurately predicting the elastoplastic behavior of frame structures containing steel-reinforced ultra-high performance concrete (SRUHPC) components is crucial for assessing the seismic safety and studying the collapse performance of buildings with such components. To expand the application range of the SRC-SFM based on DEM (Discrete Element Method), this paper introduces a UHPC constitutive model based on SRC-SFM, constructing an SFM suitable for SRUHPC components. On this basis, it also achieves the establishment of a comprehensive SRHSC model. The SRUHPC SFM model is further validated through comparisons with the hysteretic performance of SRUHPC components and plane frames of different stories.ResultsComprehensive indicators including hysteretic curves, stress-strain relationships of various fibers at the column base, energy dissipation curves, and stiffness degradation curves prove that SRUHPC-SFM can be used to simulate the hysteretic performance of SRUHPC components and SRUHPC plane frames.DiscussionThis extends the application of DEM in studying the non-linear mechanical properties of structures containing SRUHPC components before collapse, laying a solid foundation for accurate simulation of the entire collapse process of structures containing SRUHPC components using DEM.

GFRP was employed in constructions as an alternative to steel, which has many advantages like lightweight, large tensile strength and resist corrosion. Existing researches are insufficient in studying the influence of hybrid reinforced concrete composite columns encased by GFRP I-section (RCCCEG) and I-section steel (RCCCES). In this study twenty one (RC) specimens of a cross-section of 130 mm × 160 mm, with different length (long 1600 mm and short 750 mm) were encased by using I-section (steel and GFRP) and tested under various loading (concentric, eccentric and flexural loads). The test was focused on the influence of many parameters; load-carrying capacity, mode of failure, deformation and drawing an interaction diagram (N-M) for columns. The research explores the feasibility and effectiveness of the employing GFRP and steel sections. The test results concluded that all the composite columns with I-section steel presented similar failure modes to I-section GFRP composite column. Increasing in strength and ductility in short and slender reinforced concrete composite columns related to reinforced concrete columns. The eccentric load has a significant reduction in column strength, especially in slender column. The 3D FE models of (RCCC) were established by ABAQUS. (RCCC) was studied in terms of failure mode, deformation and bearing capacity also an analytical study was employed to obtain analytical results for short specimens subjected to flexural load and employing these outcomes for drawing interaction diagram (N-M) for short columns. Based on the verification of FE analysis, the experimental and theoretical results showed a good agreement.

The present analysis investigates the possibility of using a tapered mast profile for bladeless wind turbines (BWTs) to enhance the function of extracting wind energy through the phenomenon of vortex-induced vibrations. Conventional HAWTs which remain the most efficient are however, costly in maintenance, mechanically complicated and rather unfavourable to the environment. To overcome these challenges a prototype BWT with a 0.6 m tapered mast was developed for the currents using mild steel and hollow square steel sections. Wind tunnels were also used to compare stress distribution, structural deformation and vane vortex shedding for the building at different wind speeds. The maximum calculated equivalent stress on the mast was 1.63 ´ 105 Pa with the total deformation achieving 1.732 ´ 10‒6 m at a wind speed of 4 m∙s‒1. The tests have represented an independent check on mast dynamics using recorded wind at an average of 7 m∙s‒1 and have quantified the observed oscillations marking validity of the dynamic behavior observed through simulations. Piezoelectric sensors deployed to measure mechanical stress produced voltage responses of 7.68 mV, 28.865 mV and 44.915 mV at wind velocities of 5.5 m∙s‒1, 6.1 m∙s‒1 and 7.8 m∙s‒1 respectively. Findings show that wave amplitude of the oscillations increases with wind velocity and concomitantly voltage generated. The study highlights the potential of tapered mast geometries in improving structural efficiency and energy output.

In recent years, fiber-reinforced polymer (FRP) composites have been utilized to strengthen structural components to effectively tackle increased cycling loads or repair challenges caused by wear or fatigue fractures. Consequently, this research is focused on exploring existing FRP reinforcement techniques for structural steel components that have experienced fatigue damage. This research examines surface treatment techniques, adhesive curing methods, and support configurations under cyclic loading through finite element (FE) modeling of steel bridge girders alongside structural principles, focusing on fatigue performance, crack development, and failure modes. FRP-strengthening composites increase fatigue life, minimize stiffness degradation with residual deflection, postpone initial cracking, and slow the rate of crack propagation. CFRP, or prestressed carbon Fiber-reinforced polymer, is the finest choice for improvement.

Compared with ordinary steels, stainless steels possess advantages such as robust corrosion resistance, beautiful appearance, and excellent ductility. This article investigated the performance of a novel C-shaped folded flange section stainless steel beam with web stiffeners under bending and shear interaction, with a focus on the effect of the web tension field on its performance after transverse constraint. Stiffeners can effectively promote the bearing capacity of cold-formed thin-wall components, and folded flanges are convenient for connecting to floors, thus expanding the application range of stainless steel components. This study detailed the three-point bending tests conducted on specimens with shear span ratios of 1.5 and 2, as well as the numerical analysis methods employed. The experimental results of ultimate bearing capacity were compared with the predictions made by the Direct Strength Method (DSM) and Continuous Strength Method (CSM) adopted in current design codes. It was found that positioning the stiffeners closer to the compression flange enhanced the bearing capacity of the member, and this enhancement effect became more pronounced with an increase in the shear span ratio. Furthermore, the Continuous Strength Method (CSM) predicts the moment and shear bearing capacity more accurately. Furthermore, the Continuous Strength Method (CSM) provided more precise predictions of both the bending moment and shear capacity under the web tension field. The research results are helpful to provide theoretical basis and technical support for such members in engineering applications.

Abstract The configuration object of this study is a steel H‐shaped profile encased in reinforced concrete where the shear connection is obtained by rebars passing through holes in the web of the steel profile. This configuration is common for different structural typologies such as filler beam decks, slim‐floor beams, H‐pile head, or beam‐end anchorages. Experimental push‐out tests were performed at the University of Luxembourg with the objective to investigate the impact of using steel fibre reinforced concrete as an addition to the traditional bar reinforcement. The geometrical configuration was representative of the intended final application as filler beam deck and three specimens were casted with normal concrete and three specimens with steel fibre concrete. The main contributors of the shear connection resistance are surface friction at lower load levels and the reinforced concrete dowels through the web holes for higher load levels. Though a robust rebar reinforcement was foreseen, results showed a considerable enhancement of the structural performance thanks to the presence of steel fibres even for a moderate volumetric ratio. The enhanced tensile properties highly contribute to the shear resistance of the concrete matrix, ensuring higher resistance levels before the activation of shear failure surfaces. Steel fibres also confer a higher ductility to the concrete matrix particularly useful at steel‐concrete contact interfaces where high local pressures take place.

Residual stresses in cold-formed steel sections: An overview of influences and measurement techniques

The introduction of steel into Brazilian civil construction in the late 19th and early 20th centuries marked a turning point, with domestic production gaining prominence following the establishment of the National Steel Company (Companhia Siderúrgica Nacional) in 1946. Steel’s high strength and ductility have made it indispensable for large-scale projects, offering execution efficiency and recyclability. However, its high production costs and energy consumption raise environmental concerns, as the steel industry contributes significantly to global CO2 emissions. Within this context, this study investigates the influence of the end vertical member length on steel consumption and the sizing of steel sections in roof trusses. Using the Finite Element Method (FEM) through a computational tool developed in Python, 21 simulations were performed, varying the vertical member length from 0 to 100 cm in a Howe truss with a 24-meter span and a 10% slope in the top chord. The results indicated a 52% reduction in steel mass between the extreme values, highlighting the importance of geometric adjustments to optimize material consumption. Increasing the vertical member length redistributed internal forces, enabling the use of lighter sections. These findings underscore the relevance of optimization in structural design to promote sustainable solutions, reducing resource consumption and the environmental impact of steel constructions.

Precast systems are increasingly favored in modern construction to meet the growing demands for faster project delivery, cost control, and enhanced quality assurance. Yet, the feasibility of connections between precast elements remains a crucial factor affecting the overall structural performance of these systems. Considering the versatility and dimensional consistency of structural steel sections, this study introduces an emulative column-to-column hybrid connection achieved by using welding-spliced steel tubes, with a view to improving assembly efficiency and on-site quality control. Reversed cyclic loading tests were conducted on five near full-scale column specimens to assess the seismic performance of the proposed connection. Results indicated that this connection method could provide seismic performance comparable to that of the traditional cast-in-place counterpart. Nevertheless, the anchorage of the column longitudinal rebars played a critical role, as inadequate anchorages led to significant reductions in the columns’ lateral capacity. For this reason, increasing the tube thickness was shown to be insufficient as a substitute for proper anchorage detailing. Moreover, it was found that the incorporation of the welded steel tubes shifted the plastic hinge region upward, resulting in a more extended damage zone—a consequence of the localized stiffening effect. Finally, existing equations and methods are employed to evaluate the lateral strength, load-displacement response, and plastic hinge length of the tested specimens.

The axial compression capacity of steel reinforced concrete (SRC) stub columns with unsymmetrical steel sections (USSs) was investigated in this study. Axial compression tests were conducted on four SRC stub columns with USSs, and internal force analyses were conducted on a total of 22 finite-element models. The failure modes, load–displacement curves and internal forces were used to analyse the mechanical behaviour and bearing capacity of the columns under axial compression. Furthermore, the variables that influence the axial compression capacity comprising different width-to-thickness ratios of the steel flange, area ratio of the steel section to the confined concrete, web eccentricities and steel eccentricities were investigated in a parametric analysis. The results showed that, compared to SRC stub columns with symmetrical steel sections (SSSs), the columns with USSs showed slightly flexural failure. Steel eccentricity was the main factor that affected the axial compression capacity of SRC stub columns with USSs. An equation was proposed for calculating axial compression capacity of an SRC stub column with a USS considering steel eccentricity. Results calculated by the proposed formula showed better agreement with the experimental value than that calculated by the codes, and the formula is also applicable to SRC stub columns with SSSs.

ABSTRACT This research presents an experimental and analytical investigation of an interior precast beam-column connection using a hybrid steel connector. The beam-column connections were introduced with different positive and negative reinforcement alignments to achieve behaviour comparable to a monolithic reinforced concrete connection. The primary objective of this study is to examine key parameters such as load-carrying capacity, mode of failure, crack pattern, ductility, stiffness, and energy dissipation capacity in beam-column connections. Three half-scale beam-column connection specimens were tested under displacement-controlled lateral cyclic loading combined with constant axial loading. One cast-in-place control specimen and two precast specimens were tested. The control specimen was designed based on the strong-column–weak-beam concept to meet code requirements for strength, while the precast specimens were detailed to replicate this design approach. To enhance performance, the precast specimens (PBC1 and PBC2) were fabricated with different configurations, including variations in reinforcement alignment and using hybrid steel connectors of varying sizes. Considering the test variables, the above-mentioned key parameters for the control specimen were compared with those of the precast specimens (PBC1 and PBC2). The results showed that the precast specimens demonstrated enhanced strength and energy dissipation compared to the monolithic specimen, based on single-specimen test results. This clarification addresses the limited statistical representation due to using only one specimen per configuration. Using hybrid steel connectors with asymmetric detailing and varied connector heights represents a novel approach to improving seismic behaviour in interior joints. Seismic performance was further evaluated using damage indices and validated through Finite Element Analysis (FEA) using ABAQUS software. The FEA results closely correlated with the experimental results. Additionally, the analytical results help to predict the experimental results at the peak point.

The current study investigated the axial compression behavior of fully encased composite columns (FECC) reinforced with glass fiber reinforced polymer (GFRP) bars. Totally three conventional FEC columns and three FEC columns with the addition of alkali resistant glass fiber (ARGF) made with High Strength Concrete (HSC) are tested under axial compression. The inclusion of ARGF enhances the adhesion between the concrete and the steel reinforcement in the FECC. This increased bond strength facilitates a more efficient transfer of stresses and strains, thereby improving the load-carrying capacity. The dimensions of the FEC columns are 150mm x 150mm x 1000mm, and the steel section is ISMB 50mm x 100mm. All columns were designed as per Indian Standard (IS). The main parameter was studied in axial load carrying capacity, axial-deformation response, failure mode, peak ductility, and stiffness. The experimental results of conventional FEC columns were compared to those of FEC columns with the addition of AFGR. The axial load-carrying capacity and stiffness increased by 3.77% and 32.27%, respectively, while ductility decreased by 15.46% compared to conventional FEC columns. The analytical study was conducted in all columns; the analytical results were agreed to the experimental results.

The current work presents a finite element analysis (FEA) based investigation of the structural steel pipe with internal corrosion defects. A total of 27 different geometrical conditions for internal corrosion defect were considered using 3 different internal pressures of 2.2 MPa, 4.5 MPa, and 6 MPa. The validation of the FEA model was carried out using the analytical solution for failure pressure using radial and hoop stresses. The failure pressure of the uncorroded pipe was 11.5 MPa. In contrast, for pipe with internal corrosion defect having the largest defect depth (1.7 mm), largest length (454 mm), and sharpest geometry (width of 26 mm), the failure pressure from FEA was 6 MPa. The remaining strength at this boundary condition was 0.521. The radial stress influences the strain in wall thickness which was 8.8 mm and much less as compared to other dimensions of pipeline which diminishes the material's ability to resist the failure pressure. The Von-Mises stress accumulation inside the interface increases the stress intensity (K) distribution at the vicinity of the internal corrosion defect geometry vis-à-vis lowers the K-distribution just outside of the internal corrosion defect. The largest factor of safety (FOS) of 2.11 was obtained at threshold boundary conditions considering fatigue limit as the optimum stress. It is then suggested that the FOS for the "break-before-leak" leak model can be anywhere between 2.11 to 1.45 and hence the pipeline cannot burst into rapture.

Present-day high strength concrete (HSC) encased steel composite (ESC) columns play a significant role in the construction industry. ESC resists steel sections from corrosion and fire resistance, increasing the load-carrying capacity compared to conventional reinforced concrete columns. This study investigated the behaviour of high-strength concrete encased steel composite short columns subjected to axial load. This study included analytical, experimental and numerical studies. The main objectives of this study are the axial load-carrying capacity of columns, mode of failure, peak ductility and stiffness at yield and ultimate point. A total of three column specimens were chosen in this study: one is a strength concrete ESC column, the second one is a strength reinforced concrete column, and the final one is a steel column; all columns were designed with the Indian standard code. The experimental study was compared to the analytical and numerical analysis; analytical and numerical studies also help predict the experimental research. Analytical and numerical study results were highly correlated to the experimental test results.

Experimental and Finite Element Analysis on Seismic Performance of Composite Shear Walls with Embedded Cold-Formed C-Shape Steel Section

Design of a Drilling Jig for Drilling Operations on Hollow Steel Sections

This study investigates whether structural adhesives can provide reliable shear transfer in steel-concrete composite connections, focusing on how lap length affects interface capacity. A push-out test program evaluated three bonded specimens with lap lengths of 100 mm, 150 mm, and 200 mm using a two-part epoxy. Each specimen combined an IPE steel section with a plain concrete block and a 5 mm adhesive layer. Results showed sudden, brittle failure governed by the concrete close to the bonded interface for all cases. The 150 mm lap length achieved the highest measured shear stress, suggesting that bond geometry influences capacity beyond bonded area alone. The findings support prior evidence that capacity tends to saturate beyond an effective bond length and that width to length proportion can shift stress concentrations. Practical implications include selecting lap lengths that balance constructability with reduced stress peaks, improved reliability, and minimized surface preparation demands. Limitations include single tests per configuration and potential setup variability, so future work should include replication and parametric studies of width to length ratio, surface treatment, and adhesive type.

Experimental Investigation on Structural Behavior of Continuous Concrete Beams Curved in Plan Reinforced with Cold-Formed Steel C-Section

Trusses have long been integral to structural design due to their efficiency in bearing loads. However, a lack of clear guidelines for optimizing truss beams often forces engineers to compromise between performance and cost. This study addresses this gap by optimizing the shape and size of two-dimensional steel truss beams using Finite Element Analysis (FEA) with ABAQUS software under specified conditions. The analysis considered uniform vertical loads of 200 kN, 500 kN, and 200 kN applied at strategic joints, with pinned supports as boundary conditions. Four truss configurations; V-structure, V-structure with vertical members, N-structure, and K-structure were examined for stress, displacement, and critical buckling. The K-structure emerged as the optimal design, with the smallest deflection of -12.28 mm and a maximum stress of 178.85 MPa. Further, the High Edge A (HEA) 240 steel section was identified as the best cross-sectional choice, offering superior structural stability and cost-efficiency. This study demonstrates that strategic optimization of truss configurations and materials can significantly enhance performance while minimizing material use and costs. These findings have implications for safer and more economical steel truss designs, contributing to advancements in modern construction practices.

The cold-bending effect during the roll-forming process may affect the material's mechanical properties and induce residual stress in the cold-formed steel sections. Cos-α X-ray Diffraction is an appropriate method for measuring residual stress in cold-formed steel due to the materials' thinness. This method also offers excellent precision and simplicity. However, the limited penetrating ability of X-rays, which extend only a few microns, significantly hinders the measurement of residual stresses in cold-formed steel when coatings are present. Therefore, this study will implement two uncoating or de-coating techniques for measuring residual stress using the cos-α X-ray Diffraction method on the surface of cold-formed steel with a 50 μm layer of aluminum-zinc coating. These techniques include water sanding and chemical solutions. Two procedures are performed for the chemical solution: the first procedure combines a 25% hydrochloric acid (HCl) solution with a 25% ammonium hydroxide (NH4OH) solution, while the second procedure uses only a 25% hydrochloric acid (HCl) solution. This study demonstrates that the second procedure effectively removes the surface coating from cold-formed steel and provides a good classification of cos-α X-ray Diffraction intensity data related to the Debye-Scherrer ring. A combination of 25% hydrochloric acid (HCl) and 25% ammonium hydroxide (NH4OH) solution results in a mediocre classification. On the other hand, the water sanding technique produced poor classifications. Furthermore, the key to the success of the cos-α X-ray Diffraction method is removing the coating from the cold-formed steel.