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This study aims to research the development trend, research status, research results and existing problems of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

Based on the investigation and analysis of the development history, structure form, structural parameters, stress characteristics, shear connector stress state, force transmission mechanism, and fatigue performance, aiming at the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge, the development trend, research status, research results and existing problems are expounded.

The shear-compression composite joint has become the main form in practice, featuring shortened length and simplified structure. The length of composite joints between 1.5 and 3.0 m has no significant effect on the stress and force transmission laws of the main girder. The reasonable thickness of the bearing plate is 40–70 mm. The calculation theory and simplified calculation formula of the overall bearing capacity, the nonuniformity and distribution laws of the shear connector, the force transferring ratio of steel and concrete components, the fatigue failure mechanism and structural parameters effects are the focus of the research study.

This study puts forward some suggestions and prospects for the structural design and theoretical research of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

This study aims to reveal more information and understanding on performance and failure mechanisms of high strength steel endplate connections after fire.

An experimental and numerical study on seven endplate connections after cooling down from fire temperature of 550°C has been carried out and reported herein. Moreover, the provisions of European design standard for steel structures, Eurocode 3, were validated with test results of high strength steel endplate connections.

In endplate connections, a proper design using a thinner high strength steel endplate can achieve the same failure mode, similar residual load bearing capacity and comparable or even higher rotation capacity after cooling down from fire. It is found that high strength steel endplate connection can regain more than 90 per cent of its original load bearing capacity after cooling down from fire temperature of 550°C.

The post-fire performance of high strength steel endplate connection has been reported. The accuracy of Eurocode 3 for endplate connections is validated against test results.

The purpose of this paper is to investigate the static and dynamic inelastic response of rigid and semi-rigid connections of steel structures with concrete-filled steel tube (CFST) columns built in high seismic areas, and to compare it with those with open section columns.

CFST columns are frequently used in moment resistant steel frames located in seismic areas due to their inherent advantages, including their ductility, energy absorption capacity as well as their high bearing capacity. The smart combination of steel and concrete makes it possible to benefit from the advantages of both components to the maximum. This research work presents the nonlinear dynamic response of moment resistant steel frames with CFST columns, with rigid or semi-rigid connections, built in high seismic areas, according to the Algerian seismic code RPA 99/2003, European EC8 and American FEMA 356 to show the nonlinear characteristics of this type of structures, and their advantages over steel frames with open section columns.

The paper presents the advantages of using CFST columns with rigid and semi-rigid connections on the seismic response of portal steel frames. A high performance level in terms of ductility, plastic hinges distribution and their order of appearance has been obtained. It also shows the low effect of seismic loading on the structural elements with CFST columns compared to structures with open section columns.

The investigation of the numerical results has shown the possibility of their use in the seismic areas for their adequate performance, and also with respect to the design limits specified in the seismic guidelines. In addition, this study represents a first step to develop seismic performance factors for steel structures with CFST columns in Algeria, where the Algerian code do not include a comprehensive specification for the composite steel structures.

Bonded steel-concrete is one new type composite structure in civil engineering domain. Generally, for steel-concrete composite structures, the steel beam and the concrete are connected by means of shear connectors. This work consists in analyzing the design optimization of the steel-concrete composite beam connected by adhesives instead of metal connectors. The principal parameters, including elastic modulus of adhesive, the adhesive layer thickness, the bonding strength and the bonding area, which influence the mechanical behaviours of the bonded steel-concrete composite structures, have been investigated. Finally, an example of design optimization of a single span adhesive bonded steel-concrete composite beam is proposed.

The purpose of this paper is to investigate the fatigue performance of a welded detail from a composite steel-concrete railway twin girder bridge caused by a passenger train circulating at varying speeds, by identifying the dynamic amplification scenarios induced by resonance. For this purpose, the hotspot stress method is used, instead of the traditional nominal stress methods.

This paper assesses the fatigue behavior of a welded connection considering critical stress concentration locations (hotspot). Finite element analysis (FEA) is applied, utilizing both a global and a local submodel, made compatible by displacements field interpolation. The dynamic response is obtained through the modal superposition method. Stress cycles are extracted with the rainflow counting method and the fatigue damage is calculated with Palmgren-Miner’s rule. The feasibility of five submodels with different mesh densities, i.e. 1, 2, 4, 8 and 20 mm is verified.

An increase in the fatigue damage due to the resonance effect was found for the train traveling at a speed of 225 km/h. A good agreement between the computed fatigue damage for the submodels is achieved. However, a non-monotonic hotspot stress/fatigue damage vs mesh density convergence was observed with a peak observed for the 4 mm model, which endorses the mesh sensitivity that could occur when using the surface stress extrapolation detailed rules specified in the standards for the hotspot stress method.

Advanced dynamic analyses are proposed to obtain local stresses in order to apply a local method for the fatigue assessment of a bridge’s structure subjected to high-speed railway traffic on the basis of the mode superposition technique resulting in much less computing times.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect of continuity of reinforcements.

Experiments on composite beams with fin-plate joints protected only at the beam ends are conducted. The test parameter is the specification of reinforcement, which affects the rotational restraint of the beam ends. In addition, a simple method for predicting the failure time of the beam using an evaluation model based on the bending moment resistance of the beam considering the hogging moment resistance of the fin-plate joint and the reinforcement is also presented.

The test results indicate that the failure time of the beam is extended by the hogging moment resistance of the joints. This is particularly noticeable when using a reinforcing bar with a large plastic deformation capability. The predicted failure times based on the evaluation method corresponded well with the test results.

Recent studies have proposed large deformation analysis methods using FEM that can be used for fire-resistant design of beams including joints, but these cannot always be applicable in practice due to the cost and its complexity. Our method can consider the hogging moment resistance of the joint and the temperature distribution in the axial direction using a simple method without requirement of FEM.

The purpose of this paper is to report the first of four planned fire experiments on the 9.1 × 6.1 m steel composite floor assembly as part of the two-story steel framed building constructed at the National Fire Research Laboratory.

The fire experiment was aimed to quantify the fire resistance and behavior of full-scale steel–concrete composite floor systems commonly built in the USA. The test floor assembly, designed and constructed for the 2-h fire resistance rating, was tested to failure under a natural gas fueled compartment fire and simultaneously applied mechanical loads.

Although the protected steel beams and girders achieved matching or superior performance compared to the prescribed limits of temperatures and displacements used in standard fire testing, the composite slab developed a central breach approximately at a half of the specified rating period. A minimum area of the shrinkage reinforcement (60 mm²/m) currently permitted in the US construction practice may be insufficient to maintain structural integrity of a full-scale composite floor system under the 2-h standard fire exposure.

This work was the first-of-kind fire experiment conducted in the USA to study the full system-level structural performance of a composite floor system subjected to compartment fire using natural gas as fuel to mimic a standard fire environment.

This paper aims to study, the effects of opening shape, size and position as well as the aspect (height-to-length) ratio on the shear capacity, stiffness, ductility and energy dissipation capacity of triple-skin profiled steel-concrete composite shear wall (TSCSW) and investigate and compare them to those of concrete-stiffened steel plate shear walls (CSPSW). Two kinds of opening, circular and square, with different sizes and positions and two aspect ratios of 1:1 and 3:1 are considered in the simulations.

This study presents a novel TSCSW and compares its behavior with the existing CSPSW under the effect of monotonic and cyclic loadings. TSCSW is composed of three corrugated steel plates filled with concrete. The two external side plates are connected to the concrete core by means of several intermediate fasteners and the third one is an inner steel plate embedded within the concrete panel. The internal plate is a buckling restrained plate surrounded by concrete. This is the main superiority of TSCSW over other kinds of existing composite shear walls.

The results show that the shear capacity and the energy dissipation capacity of the proposed composite wall, TSCSW, are respectively about 16 and 12% higher than those of CSPSW when there is no opening. If an opening is considered in the wall, as the size of the opening is increased, the shear capacity, stiffness, ductility and absorbed energy of the two walls are decreased similarly. The destructive effect of square openings on the performance of the walls is more than that of circular openings.

This is an original work.

OpenSees is an open-source object-oriented software framework developed at UC Berekeley. The OpenSees framework has been recently extended to deal with structural behaviour under fire conditions. This paper summaries the key work done for this extension and focuses on the validation and application of the developed OpenSees to study the behaviour of composite steel-concrete beams under fire conditions. The performance of the developed OpenSees are verified by four mechanical tests and two fire tests on simply supported composite beams. A parametric study is carried out using OpenSees to study the influence of boundary condition as well as composite effect of slab on the behavior of composite beams exposed to fire. The stress and strain along the beam section is output and compared with yield stress limit at elevated temperature to explain these influences in detail. The results show that the stress distribution in the web of the steel beam is more complex due to the support effects.