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The effect of bolt stripping failure on the ductility of steel end plate beam-column connections has received relatively little investigation to date. The objective with the present work is to establish a validated numerical model of end plate connections at elevated temperatures, which predicts the mechanical behaviour and failure modes observed in the experimental tests including the bolt stripping failure. Furthermore, the validated FE model was used to investigate the effect of stripping failure on both the rotational and load-bearing capacity of end plate connection.

The analysis was conducted on a validated numerical model of end plate connections at elevated temperatures, which predicts the mechanical behaviour and failure modes observed in the experimental tests including the bolt stripping failure. The material was modelled considering ductile damage initiation and evolution featured in ABAQUS/Standard.

This study demonstrates that thick end plates can prevent stripping failure which significantly improves the rotational capacity of the connection. This failure mode can develop readily with thin end plates; however the effect is often unrealistically mitigated through idealised experimental tests. The rotational capacity of a connection can be 5.0 times higher if stripping failure is avoided, particularly at elevated temperatures. Eurocode 3 part 1.8 does not consider the possibility of stripping failure when discussing the requirements for plastic analysis. It is concluded in the present study that by allowing for the possibility of bolt stripping, the mode of failure can often shift from end plate failure to bolt stripping, this in turn significantly reduces the connection rotational capacity.

The effect of bolt stripping failure on the ductility of steel end plate beam-column connections has received relatively little investigation to date.

Concrete-filled steel tube structures are widely used for their high bearing capacity, good plasticity, good fire resistance and optimal seismic performance. In order to give full play to the advantages of concrete-filled steel tube, this paper proposes a prefabricated concrete-filled steel tube frame joint.

The concrete-filled steel tube column and beam are connected by high-strength bolted end-plate, and the steel bars in the concrete beam are welded vertically with the end-plates through the enlarged pier head. In addition, the finite element software ABAQUS is used numerically to study the seismic performance of the structure.

The ductility coefficient of the joint is in 1.72–6.82, and greater than 2.26 as a whole. The equivalent viscous damping coefficient of the joint is 0.13–3.03, indicating that the structure has good energy dissipation capacity.

The structure is convenient for construction and overcomes the shortcomings of the previous on-site welding and on-site concrete pouring. The high-strength bolted end-plate connection can effectively transfer the load, and each component can give play to its material characteristics.

The purpose of this study is to put forward a high-strength bolt end-plate connection of prefabricated concrete beam-column joint and carry out the pseudo-static test.

ABAQUS finite element software is used to study the fire resistance performance of high-strength bolt end-plate prefabricated joint. This mainly considers the influence of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness.

The results show that the thickness of end-plate and steel hoop has a certain effect on the fire resistance. The change of screw preload has little effect on the fire resistance limit. Compared with the cast-in-place concrete beam-column joint, the deformation trend of column-beam end of the fabricated joint is basically the same as that of cast-in-place joint.

To study the mechanical performance of this kind of joint more comprehensively, the finite element software is used to study the prefabricated concrete beam-column joint with end-plates, and the effects of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness on the fire resistance of joints are mainly considered.

The paper aims to report a fire test conducted on a three-dimensional frame in order to investigate the behaviour of bare steel flush end-plate connections with relatively low thickness at elevated temperatures.

A half-scale model was fabricated and exposed to modified (scaled) ISO 834 heating curve using a semi-open furnace. The maximum temperature inside the furnace reached 1,026 °C.

The rotations of connections are reported and compared with those of a previous study on an exactly the same model with thick end-plates. Various modes of failure such as local buckling of the beams flanges and lateral-torsional buckling of beams were observed during the test. Finally, the structure collapsed after 29 min of heating due to the fracture of weld between one of the beams and one of its attached end-plates whilst the other beam had undergone a maximum deflection of 35 cm (≈ 1/6 span length). Other observed failure modes included bolt fracture, bolt thread stripping and large inelastic deformation of the end-plates.

Although the adoption of thin end-plates increased the rotational capacity of the connections, it did not improve the robustness of the structure under fire conditions.

Basically, connections are used to transfer the force supported by structural members to other parts of the structure. The flush end-plate bolted beam to column connection is one type that has been widely used because of its simplicity in fabrication and rapid site erection. The purpose of this study is to determine the moment-rotation curve, moment of resistance (MR) and mode of failure, and the results were compared with existing results for normal flat web connections.

In this study, the connection modeled was the flush end-plate welded with triangular web profile (TriWP) steel beam section and then bolted to a UKC column flange. The bolted flush end-plate semi-rigid beam to column connection was modeled using finite element software. The specimen was modeled using LUSAS 14.3 finite element software, with dimensions and parameters of the finite element model sizes being 200 × 200 × 49.9 UKC, 200 × 100 × 17.8 UKB and 200 × 100 with a thickness of 20 mm for the endplate.

It can be concluded that the MR obtained from the TriWP steel beam section is different from that of the normal flat web steel beam by 28%. The value of MR for the TriWP beam section is lower than that of the normal flat web beam section, but the moment ultimate is higher by 21% than the normal flat web. Therefore, it can be concluded that the TriWP section can resist more acting force than the normal flat web section and is suitable to be used as a new proposed shape to replace the normal flat web section for a certain steel structure based on the end-plate connection behavior.

As a result, the TriWP section has better performance than the flat web section in resisting MR behavior.

The purpose of the paper is to predict the aerodynamic performance of a complete scale model H-Darrieus vertical axis wind turbine (VAWT) with end plates at different operating conditions. This paper aims at understanding the flow physics around a model VAWT for three different tip speed ratios corresponding to three different flow regimes.

This study achieves a first three-dimensional hybrid lattice Boltzmann method/very large eddy simulation (LBM-VLES) model for a complete scaled model VAWT with end plates and mast using the solver PowerFLOW. The power curve predicted from the numerical simulations is compared with the experimental data collected at Erlangen University. This study highlights the complexity of the turbulent flow features that are seen at three different operational regimes of the turbine using instantaneous flow structures, mean velocity, pressure iso-contours, blade loading and skin friction plots.

The power curve predicted using the LBM-VLES approach and setup provides a good overall match with the experimental power curve, with the peak and drop after the operational point being captured. Variable turbulent flow structures are seen over the azimuthal revolution that depends on the tip speed ratio (TSR). Significant dynamic stall structures are seen in the upwind phase and at the end of the downwind phase of rotation in the deep stall regime. Strong blade wake interactions and turbulent flow structures are seen inside the rotor at higher TSRs.

The computational cost and time for such high-fidelity simulations using the LBM-VLES remains expensive. Each simulation requires around a week using supercomputing facilities. Further studies need to be performed to improve analytical VAWT models using inputs/calibration from high fidelity simulation databases. As a future work, the impact of turbulent and nonuniform inflow conditions that are more representative of a typical urban environment also needs to be investigated.

The LBM methodology is shown to be a reliable approach for VAWT power prediction. Dynamic stall and blade wake interactions reduce the aerodynamic performance of a VAWT. An ideal operation close to the peak of the power curve should be favored based on the local wind resource, as this point exhibits a smoother variation of forces improving operational performance. The 3D flow features also exhibit a significant wake asymmetry that could impact the optimal layout of VAWT clusters to increase their power density. The present work also highlights the importance of 3D simulations of the complete model including the support structures such as end plates and mast.

Accurate predictions of power performance for Darrieus VAWTs could help in better siting of wind turbines thus improving return of investment and reducing levelized cost of energy. It could promote the development of onsite electricity generation, especially for industrial sites/urban areas and renew interest for VAWT wind farms.

A first high-fidelity simulation of a complete VAWT with end plates and supporting structures has been performed using the LBM approach and compared with experimental data. The 3D flow physics has been analyzed at different operating regimes of the turbine. These physical insights and prediction capabilities of this approach could be useful for commercial VAWT manufacturers.

This study presents a numerical modeling by the finite element method of galvanic corrosion between the bolt (cathode) and the end plate (anode). The bolt is made of three types of stainless steel: austenitic (SS304L, SS316L), martensitic (SS410, SS420) and duplex (32,101), and the end plate is made of carbon steel (S235JR).

Finite element modeling.

The results obtained show, on the one hand, that this corrosion rate increases as the conductivity increases, on the other hand, the stainless steels having the highest corrosion resistance causes a considerable loss of mass of the end plate and subsequently a decrease in the lifetime of the bolted joint.

The galvanic corrosion of beam to column bolted joint with end plate, used in steel structures, was studied in order to determine the corrosion rate of the end plate and subsequently to predict the total lifetime of the bolted joint.

Validate the resistance of bolted connections in terms of stresses, resistant moment and contact pressure.

Finite element modeling of corroded bolted joint.

The three types of corroded assemblies are resistant to the applied loads.

The research is original, it studies the stress corrosion cracking of a bolted assembly's end plate by the finite element method.

AS in the case of end‐plate fins, inset fins have the effect of increasing the effective aspect ratio of the tail plane, but to a somewhat less extent. The tail with fins will be compared with an untwisted elliptical tail without fins, because this method of comparison is very clear and being also used to compare wings of different shapes is familiar to people concerned with aerodynamic problems.

This paper presents a finite element analysis procedure developed to study the behavior of a flexible end-plate connection between steel beams and a column at elevated temperatures and generates temperature-rotation diagrams that describe the behavior of the connection. The analysis used a highly detailed three dimensional finite element model that is created using the commercial ABAQUS software. The steel connection properties are selected in a way that reflects commonly used connections in steel framed buildings.

The results of the finite element model are calibrated and compared to the results of experimental fire tests conducted on similar connections. The results show that the predicted behavior of the joints is in a good agreement with actual behavior of the joints. A regression model is developed to describe the behavior of flexible end-plate joints in fire.