Beam Column Research Articles

Mechanical Properties of Double-Layer Riveted Aluminum Roofing Panels with Curved Surfaces

In recent years, aluminum alloy has been increasingly used in building structures, becoming an important construction material for metal structures. Currently, aluminum alloy is commonly used in buildings as beam–column components, profiled roof panels, and door and window frames, among other forms. However, there is limited research on the mechanical properties of aluminum alloy roof panels with irregular curved surfaces. In this study, a full-scale curved double-layer anisotropic riveted aluminum alloy roof panel was subjected to a load test to analyze its deformation patterns and failure mechanisms. The results indicate that the load-bearing capacity of the roof panel meets the design requirements. During failure, neither the upper nor lower layers of the panel enter the plastic deformation stage, indicating sufficient safety redundancy. The failure mode observed is a ductile failure with noticeable deformation with the weak points of the component being the riveted connections of the stiffeners. A finite element model was established for numerical simulation and the results matched well with the experimental data. Finally, a theoretical calculation for the ultimate load-bearing capacity of the roof panel was derived, providing a reference for design purposes.

A Survey Report On Stress Level's Effect on Outside Beam Column Joints While Remodeling

A Survey Report On Stress Level's Effect on Outside Beam Column Joints While Remodeling

Experimental investigation of assembly-oriented steel column-beam connection with transverse reverse channels for prefabricated structures

The purpose of this study is to experimentally investigate the mechanical behaviour of the innovative steel column-beam connection involving transverse reverse channels in prefabricated structures with the aim of improving the assemblability during the construction processes. A series of experiments were performed on steel square hollow section (SHS) column and H-section beam connection involving three different transverse reverse channel configurations, i.e., unstiffened transverse reverse channel (UTC), between-channel stiffened (BCS) transverse reverse channel, and in-channel stiffened transverse reverse channel (ICS). The traditional connection involving vertical reverse channel (VRC) was also tested as the control to evaluate the mechanical performance of the new column-beam design, such as flexural resistance, strain distribution and failure modes. The experimental results demonstrate that stiffening the transverse reverse channels internally (ICS) could significantly strengthen the flexural resistance of the connection and the out-of-plane rigidity of the channel web. For example, the flexural resistance of ICS connection is more than 50% and 100% higher than that of the VRC and UTC connection, respectively. However, stiffening between the two transverse reverse channels externally (BCS) has little influence in the flexural resistance of the connection. The failure of the ICS connection is mainly due to the buckling of the beam, while UTC and BCS connections fail because of excessive deformation of the transverse reverse channels. Theoretical formulas can conservatively estimate the bending bearing capacity of those connections.

Effect of Geometric Parameters on the Behavior of Eccentric RC Beam–Column Joints

Over the last century, the seismic behavior of reinforced concrete (RC) beam–column joints has drawn many researchers’ attention due to their complex stress state. Such joints should possess sufficient capacity and ductility to ensure integrity and safety when subjected to cyclic loading during seismic events. In the literature, while most studies have focused on the behavior of concentric beam–column joints, few studies investigated the response of eccentric beam–column joints, in which the beam’s centerline is offset from the centerline of the column. Recent earthquakes demonstrated severe damage in eccentric beam–column joints due to their brittle torsional behavior, which may threaten the ductility required for the overall structural performance. To investigate the effect of brittle failure on the strength, ductility, and stability of eccentric beam–column joints, nonlinear finite element (FE) models were developed and validated. The FE model was employed to study the effect of some geometric parameters on the global and local behaviors of beam–column joints, including the joint type (exterior and interior), the column aspect ratio, and the joint aspect ratio. The results show that the joint aspect ratio, which is the ratio of beam-to-column depth, has a predominant effect on the failure behavior of the joint. Additionally, the increase in column aspect ratio alters the failure mode from brittle joint shear failure to ductile beam-hinge, although there is an increase in the joint torsional moment. The current study also showed that interior joints exhibited a higher out-of-plane moment as well as more extensive column torsion cracks compared to exterior joints.

Exploration of the Relationship Between Tyndall Effect and Moisture Content in Transformer Oil

Moisture content in oil detection technology such as offline method and online monitoring method has several shortcomings. In this paper, the Tyndall effect of moisture content in transformer oil was excited by a laser with a wavelength of 633 nm, and the relationship between Tyndall effect and moisture content in transformer oil was investigated. The relationship between the grayscale of laser beam column and particles in oil and the relationship between the grayscale of laser beam column and temperature are also investigated. It was found that withstand voltage of the oil was negatively correlated with the gray pixel statistics of the light column, while the micro water content was positively correlated with the pixel statistics of the light column. The attenuation of the light column is only related to particle size. When the micro water content is below 10 ppm, the light column will have a significant brightening process with the increase of temperature, but it will gradually slow down above 10 ppm. The statistical value of gray pixels and the proportion of gray intervals can be used to moisture content determination. This method provides a new direction for the insulation performance detection technology of transformer oil.

The Effect of ECC Materials on Seismic Performance of Beam—Column Subassemblies with Slabs

The main objective of this investigation was to study the influence of an Engineered Cementitious Composite (ECC) on the seismic performances of beam–column–slab subassemblies. Tests and simulations were conducted on several models. The bearing capacity of the ECC model was 15% higher than that of the RC member, the deformability increased by 19%, and the energy dissipation capability increased by 34%. The use of an ECC in the slab could reduce the contribution of the reinforced bars in the slab to the flexural strength of the beam. At a drift of 2%, the range of the yielding bars in the slab of the RC models was 5h to 6h. However, the yield range of reinforcement in the slab of the ECC models was nearly 3h. As a result, the ECC subassemblies were prone to reach a “strong column and weak beam” yield mechanism.

Redesign Struktur Gedung Madrasah Aliyah Madrasatul Qur’an Tebuireng Jombang Dengan Penggunaan Beton Pracetak

Precast concrete is a concrete structure construction technology with more printed components in the factory. Here the researcher takes into account to determine the planning of structural elements using precast concrete and its connections. The Madrasatul Qur'an MA Building in Nanggungan Village was used as the object of research to take into account floor plates, beams and columns, with reference to SNI 2847 – 2019, aspects of repetition, connections on beams, columns (Crobel) and floor plates. The calculation results on a 20 cm thick plate + overtoping with repeating plates of dimensions of 15 cm and 5 cm, overtoping using pedestal reinforcement D8 – 135 mm in the X direction, using wermesh D8 – 135 mm on the pedestal in the Y direction. planned 2 models of beam dimensions of 40 cm x 60 cm, upper reinforcement 5 D16 pedestal, 4 D16 field, lower reinforcement 4 D16 pedestal, 5 D16 pitch, Ø 10 – 150 fulcrum, Ø 10 – 150 pitch, waist reinforcement 2 D13 fulcrum, 2 D13. Beam model 2 upper reinforcement 3 D16 pedestal, 3 D16 pitch, rebar Ø 10 – 150 fulcrum, Ø 10 – 150 pitch, waist reinforcement 2 Ø 13 fulcrum, 2 Ø 13 pitch. The connection between the beam and the plate relies on a pedestal mounted lengthwise, the connection of the column beam uses a short console.

ABAQUS-based hysteresis performance analysis of thorough-diaphragm bolted connection between concrete-filled steel tubular column and steel beam

Concrete-filled steel tube can effectively improve the compressive strength of members, so it is widely used in high-rise buildings, bridges and tunnels. However, there are only limited studies on the hysteresis performance of through-diaphragm plates in steel pipe concrete. In light of the current situation, this paper establishes a model of thorough-diaphragm-diaphragm bolted connection TDBC structure using numerical simulation software ABAQUS, conducting monotonic loading and cyclic displacement loading on it to study the hysteretic performance of this structure. The results reveal that the semi-rigid connection of TDBC contributes to the outwards displacement of the plastic hinge in the beam-column joint, indicating a hysteretic good performance. Furthermore, this study also finds that the flange and web area of steel beams present obvious ductile damage characteristics, which is in line with the design philosophy of strong joints and weak members, reproducing the actual damaging process to a certain extent.

Buckling resistance of hot‐finished CHS beam‐columns using FE modelling and machine learning

AbstractThe use of circular hollow sections (CHS) has increased in recent years owing to its excellent mechanical behaviour including axial compression and torsional resistance as well as its aesthetic appearance. They are popular in a wide range of structural members, including beams, columns, trusses and arches. The behaviour of hot‐finished CHS beam‐columns made from normal‐ and high‐strength steels is the main focus of this article. A particular attention is given to predict the ultimate buckling resistance of CHS beam‐columns using the recent advancement of the artificial neural network (ANN). Finite element (FE) models were established and validated to generate an extensive parametric study. The ANN model is trained and validated using a total of 3439 data points collected from the generated FE models and experimental tests available in the literature. A comprehensive comparative analysis with the design rules in Eurocode 3 is conducted to evaluate the performance of the developed ANN model. It is shown that the proposed ANN‐based design formula provides a reliable means for predicting the buckling resistance of the CHS beam‐columns. This formula can be easily implemented in any programming software, providing an excellent basis for engineers and designers to predict the buckling resistance of the CHS beam–columns with a straightforward procedure in an efficient and sustainable manner with least computational time.

Seismic Response and Recentering Behavior of Reinforced Concrete Frames: A Parametric Study

The inelastic response of reinforced concrete (RC) frames under seismic loading is influenced by mechanical and geometrical properties and by the reinforcement arrangement of the beam–column members. In this paper, the seismic response and recentering behavior of RC frames is investigated numerically via cyclic pushover analysis and described by means of three synthetic behavioral indexes, namely a recentering index, a hardening index, and a ductility index. A fiber–hinge formulation is used to describe the inelastic behavior of the RC elements, and the versatile pivot hysteresis model is implemented at the material level to capture the possible pinching effects ascribed to the weak transverse reinforcement and to poor construction details that might be observed in the existing RC structures. This model is first validated against the experimental results from the literature and then applied, within a wide parametric study, to a set of 80 RC frame scenarios featured by various combinations of axial load levels and reinforcing details. As the output of this parametric study, practical design abacuses are constructed to describe the trends of the above-mentioned behavioral indexes, which are usefully related to specific mechanical and loading features of the analyzed RC frames. The reliability of the obtained results and the usefulness of the constructed abacuses in anticipating the overall cyclic behavior of a generic RC building, depending on the actual mechanical parameters of the RC sections at each story level, is finally demonstrated through a nonlinear time history analysis of an eight-story RC frame, representative of the substandard RC frames built in the 1970s in Italy.

Numerical Investigation on the Performance of Exterior Beam–Column Joints Reinforced with Shape Memory Alloys

Upgraded design standards coupled with the damage caused by natural disasters have led to the development of smart materials with the potential to modernize current construction practices. This investigation proposes a nonlinear finite element (FE) model for evaluating the performance of beam–column joints (RC-BCJ) reinforced with shape memory alloys (SMA) and steel rebars. The model was validated based on accredited experimental data, followed by parametric analysis in ABAQUS to optimize the use of SMA bars for enhancing the seismic resistance of RC-BCJ without compromising their energy dissipation capacity. Parameters investigated include the (a) SMA–steel reinforcement ratio, (b) lengths of SMA bars, (c) elastic modulus of SMA, (d) compressive strength of concrete, and (e) axial load applied on the column. The finite element simulation results indicated that the model was capable of predicting the optimum length of SMA bars sufficient for relocating the plastic hinge away from the face of the column along the beam. Further, simulation results proved that the use of SMA bars in conjunction with steel reinforcement could be considered as an effective tool for enhancing the seismic performance of RC-BCJ joints. Among the parameters investigated, high-strength concrete was the most effective in improving joint resistance.

Seismic behavior of RC-SMF and IMF corner beam–column connections subjected to unidirectional and bidirectional lateral loads

Failure of beam–column connections can lead to partial and complete building collapse during severe earthquakes. Corner beam–column connections may be more vulnerable during earthquakes because they must withstand bidirectional loading transferred from nearby beams and columns. Furthermore, horizontal torsion exacerbates the damage to corner beam–column connections compared with other components. The objective of this study is to explore the seismic performance of corner beam–column connections in reinforced concrete intermediate moment frames (IMFs) and special moment frames (SMFs). Four full-scale beam–column connection specimens are fabricated and tested under two different loading types (unidirectional and bidirectional loading). It is observed that the strength and deformation capacity of the specimens were strongly affected by the type of loading (unidirectional and bidirectional lateral loading) and the reinforcement details (SMF, IMF). All corner connection specimens failed by joint shear failure irrespective of loading type and reinforcement detail.

Axial compressive performances of thin-walled steel tube confined steel-reinforced concrete columns after fire exposure

The thin-walled steel tube confined steel-reinforced concrete (STCSRC) column can efficiently utilise the confinement effect of steel tube on concrete. The local buckling of external thin-walled steel tubes can be delayed or avoided owing to their discontinuity at beam–column joints, thus, the structural performances of thin-walled STCSRC columns are improved. To date, the behaviour of thin-walled STCSRC columns after fire exposure under axial load has not been reported. Experimental and theoretical studies of axially-loaded circular thin-walled STCSRC stub columns were conducted in this paper, exploring mechanical performance indexes and mechanisms after fire exposure. A total of eighteen thin-walled STCSRC stub columns were designed, considering the parameters of the steel tube to concrete area ratio, heating time, and strength of the concrete. To better comprehend the behaviours of thin-walled STCSRC stub columns after fire exposure, detailed discussions in terms of the temperature distribution, failure modes, load–axial strain response, stresses of steel tubes, and load proportion of each component are presented. The heating test results reveal that the maximum temperature is lower and the time to reach the peak temperature is longer when measuring points are closer to the centre of the cross-section. The thin-walled STCSRC stub column after fire exposure presents shear failure under axial compression. The longer the heating time, the earlier the shear slippage line appears. Compared with the specimen at room temperature, the residual compressive resistance and stiffness reduce with increasing heating time. The ductility of the thin-walled STCSRC stub column improves when increasing the heating time. In addition, the diameter of the cross-section, H-shaped steel to concrete area ratio, and concrete strength have beneficial effects on residual axial load capacities and stiffnesses. Moreover, simplified calculation methods were assessed to predict the residual axial load capacities and stiffnesses of thin-walled STCSRC stub columns.

Simplified shear wall building model for design optimization

Structural design can be inefficient due to its manual and iterative nature, requiring costly and time-consuming revisions by experienced engineers; thus, there is a growing demand for automated and intelligent design approaches. In light of these factors, we propose a simplified model of shear wall buildings based on connected 3D beam columns to quickly derive the fundamental period, base shear, and moment. Our approach formulation considers an initial topologic configuration of the shear wall rectangular members, featuring intricate element connectivity and variable layout for the basement, first, and typical floors, offering a flexible approach to handle inputs from various sources, like grid-based layouts or vectorized image floor plans. Concerning the model, the column-based design yields an adequate estimation of the structure's fundamental translational period, with an R2 of around 0.7 and a roof displacement with an R2 of 0.85. Our findings, coupled with an average computing time of 1.6 s, enable the model integration into machine learning pipelines or the swift optimization of solutions by assembling fitness functions that consider parameters like building weight, roof displacement, or base shear and moment, ultimately reducing search space and saving costs in the design process.

Construction of Lanthanide Magnetic Bio-Based Porous Carbon Materials with Beam and Column Structure and Its Synergistic Adsorption Performance.

Biochar porous carbon material (BPCM) has extraordinary adsorption properties and is being widely used in different fields around the world. The pore structure of BPCM is liable to collapse, and mechanical properties are inferior; hence, the focus is on developing a new ″powerful″ structure of functional BPCM. Rare earth elements with characteristic f orbitals are used as pore and wall strengthening units in this work. The new ″beam and column structure″ BPCM was synthesized by the aerothermal method, and then, the magnetic BPCM was prepared. The results showed that the designed synthesis route was reasonable, BPCM with a steady-state beam and column structure was attained, and the La element played a stabilizing role in maintaining the overall BPCM. The La hybridization exhibits the characteristic of ″the stronger column and weaker beam″, and the La group is the ″column″ to strengthen the BPCM as the ″beam″. The functionalized BPCM (lanthanum-loaded magnetic chitosan-based porous carbon materials, MCPCM@La2O2CO3) obtained exhibited a transcendent efficient adsorption capacity with an average adsorption rate of 6.640 mg·g-1·min-1 and over 85% removal of different types of dye pollutants, which exceeded the adsorption performance of the materials of most other BPCMs. Ultrastructural analysis revealed that MCPCM@La2O2CO3 has a huge specific surface area of 1458.513 m2·g-1 and a magnetization value of 16.560 emu·g-1 for MCPCM@La2O2CO3. A new theoretical model for the adsorption of MCPCM@La2O2CO3 (multiple adsorption coexistence equation) was established. The theoretical equations clarify that the mechanism of pollutant removal by MCPCM@La2O2CO3 is different from the traditional adsorption model, presenting a mechanism of coexistence of multiple adsorption types, displaying a monolayer-multilayer adsorption mechanism, influenced by the synergistic effects of H bonding, electrostatic attraction, π-π conjugation, and ligand interaction. The rapid coordination of the d orbitals of La is an obvious factor in enhancing the adsorption efficiency.

Review on Analysis of RCC beam, Column Joint and RCC Shear wall using FRP strengthening on Ansys Software

Abstract: After occurrence of recent earthquakes in the most of world parts, scientific committees for reducing natural disasters and research centers declared based performance design, investigation faults, retrofitting, rehabilitation, new researches are related to strengthening of structures, notice performance, importance of structure, surface of earthquake levels, considering economic and feasibility. One of streningthening method of RC frame is using FRP laminates. Beam and column where intersects is called as joint or junction. The different types of joints are classified as corner joint, exterior joint, interior jointetc. on beam column joint applying quasi-static loading on cantilever end of the beam. and study of various parameters as to be find out on corner and exteriorbeam column joint i.e. maximum stress, minimum stress, displacement and variation in stiffness of beam- column joint can be analyzed in Ansys software (FEM Software) RC shear walls are considered one of themain lateral resisting members in buildings. In recent years, FRP has been widely utilized in order to strengthen and retrofit concrete structures. Significant experimental research has been conducted over the past three decades on hysteretic behavior of beamcolumn joints of RC frames under cyclic displacement loading. The various research studies focused on corner and exterior beam column joints and their behavior, support conditions of beam-column joints. Some recent experimental studies, however, addressed beam-columnjoints of substandard RC frames with weak columns, poor anchorage of longitudinal beam bars and insufficient transverse reinforcement. the behavior ofexterior beam column joint is different than the corner beam column joint.

The shear strength of existing non-seismic RC beam-column joints strengthened with CFRP Sheets: Numerical and analytical study

A key part of RC structure seismic performance is the effective distribution of earthquake forces across all resistance elements through reinforced concrete (RC) beam-column (B-C) joints. By virtue of their ease of implementation and convenient material properties, Carbon-Fiber-Reinforced Polymers (CFRP) are highly utilized for strengthening existing structures with inadequate reinforcement or insufficient confinement. Previous experimental research revealed that debonding failure widely occurs on CFRP shear-strengthened B-C joints. The experimental research as well showed the value of column axial load makes a great contribution to such joint’s failure mode. Using CFRP U-jacketing to strengthen non-seismically B-C joints, this article presents a non-linear, two-dimensional FE model for investigating shear behavior. The developed FE model considered the adhesive layer between CFRP sheets and concrete to capture the debonding and a bond-slip model was implemented between concrete-to-CFRP sheets using connector elements. The FE results were verified versus experimental works from literature to prove the proposed FE model's accuracy with appreciate to load-deformation relation and failure modes. Depending on the verified FE model, a parametric study on shear-strengthened RC B-C joints with CFRP U-jacketing with free and fixed ends was performed below monotonic loading. In the existing study, several parameters, including column-to-beam flexural strength ratio (over strength ratio), concrete strength, and value of column axial load, were investigated on the structure's strength and ductility. Using the developed strut-and-tie model (STM), new design equations were proposed to calculate strengthened RC B-C joint's shear strength using CFRP. The proposed equations incorporate the interfacial bond among concrete and CFRP effect, as well CFRP sheet end boundary (free or fixed). The developed design equation’s ability to estimate shear strengths of strengthened B-C joints with CFRP was verified through experimental works and FE results. It was evident from verification results that the produced design equations were compatible with experimental and FE model results.

Numerical analysis of steel beam–column connection under cyclic loading with dog bone type fuses

Numerical analysis of steel beam–column connection under cyclic loading with dog bone type fuses

A Review Assessment of Fiber-Reinforced Polymers for Maritime Applications

Composite materials, comprised of fibre-reinforced polymers, offer a high strength-to-weight ratio, making them excellent for the building of complex, lightweight structures in several industries, including the marine industry. There is an improvement in fuel efficiency and cost-effectiveness in general marine component developments as a result of the lightweight and flexible design characteristics. Fibre-reinforced polymer (FRP) composites are often used to construct boats, ships, and other marine compounds, such as the hull, column beams, piling structures, and other internal ship components, since they meet the aforementioned characteristics. In terms of durability, rigidity, and corrosion resistance, these FRPs may readily replace their conventional metal counterparts. So, thisreview gives an overview of FRP composites' application in marine industries for various potential applications. Fibre-reinforced polymer composites offer a significant advantage in strength and weight when compared to conventional materials.

A Review on Mechanical and Structural Performances of Precast Concrete Buildings

In recent decades, precast concrete buildings have undergone significant development, attracting considerable academic attention to their mechanical performances. Unlike cast-in-situ buildings, precast buildings are assembled on site by connecting precast components using mechanical devices or on-site casted joints, which makes the connections particularly important for overall structural performances. This study presents a comprehensive review of the mechanical performances of precast buildings, with a specific focus on various types of connections and their structural properties. This study reviews the mechanical performances of building connections using dry, wet, and/or hybrid methods between pre-manufactured components, e.g., beam–column joints, wall–panel connections, and column/wall–foundation connections. Both experimental and numerical investigations are reviewed. The paper provides a valuable reference regarding the mechanical performances of precast concrete buildings.