Steel-concrete Composite Structures Research Articles

Mechanical behavior of a novel compact steel-UHPC joint for hybrid girder bridges: Experimental and numerical investigation

Ultra-high-performance concrete (UHPC) has recently been applied as an alternative to normal concrete in steel-concrete composite structures. In this paper, a novel compact steel-concrete joint with UHPC grout, which utilizes shear connectors, a bearing plate and a simple I-shaped steel girder, is proposed for long-span railway hybrid girder bridges. To investigate the mechanical behavior and force transfer characteristics of the proposed compact steel-UHPC joint (CSUJ), a model test with reduced scale and push-out tests of its main force transfer components were conducted. The specimens' failure model, load-interface slip, and strain development were compared and discussed in detail. Furthermore, a finite element model of the CSUJ was established to investigate the internal damage evolution and the load transfer path. The test results indicated that the steel-UHPC joint possessed excellent axial stiffness and cracking resistance. The axial stiffness before cracking is 2.6 times that of the steel-concrete joint prototype with C60 concrete grout. Upon loading, the filled-in UHPC of the CSUJ was in elastic compression. In the ultimate limit state, the steel-UHPC joint exhibited great integrity, and the ultimate failure mode of the CSUJ was controlled by the adjacent axially loaded steel beam segment. Results of push-out tests showed that the force transfer component with perfobond leiste (PBL) connectors demonstrated greater ductility than other transfer components. In terms of the force transfer rate and uniformity, the proposed CSUJ provides desired stress distribution and force transfer behavior. The shear connectors, bearing plate, and end face of the I-girder transferred 49%, 35%, and 16% of the total axial force, respectively.

Effect of corrugated steel angle on the damage characteristics and anti‐explosion performance of corrugated steel–concrete composite structures

SummaryA three‐dimensional refined numerical simulation model of a corrugated steel–concrete slab composite structure under contact explosion load was established by the finite element model and smoothed particle hydrodynamics(FEM‐SPH) coupling method to explore the anti‐knock properties of corrugated steel reinforced concrete slabs with different angles. The effects of corrugated steel angle on the dynamic response, damage evolution characteristics, damage mode, anti‐knock property, and propagation mechanism of the shock wave in the composite structure were investigated, and the damage prediction and anti‐knock property evaluation of the composite structure were carried out. The results show that the simulation results of the mid‐span displacement of the corrugated steel are consistent with the experimental results, and the maximum error is 2.3%, which verifies the effectiveness of the contact explosion simulation process. The mid‐span displacement, peak stress, acceleration at the center point, and energy absorption value of 90° corrugated steel are 17.9%, 70.5%, 88.6%, and 59.4% lower than those of 30° corrugated steel. The damage range of the composite structure gradually decreases with increasing angle of the corrugated steel. The failure volume of the concrete slab reinforced by corrugated steel with different angles decreases with increasing angle of the corrugated steel, and the energy absorption value of the composite structure increases with increasing of angle of the corrugated steel, mainly because the corrugated steel increases the number of reflections of the stress wave. The research results can provide a theoretical basis for the application of composite structures in the field of structural anti‐explosion protection.

Flexural behavior of the corrugated steel-concrete composite structures with the polyurethane concrete (PUC)

The use of polyurethane concrete (PUC) with a high compressive strength together with a corrugated steel plate (CSP) with a high tensile strength can improve the bending capacity of the corrugated steel-concrete composite structures. Although the PUC is lighter than normal concrete, its compressive, tensile, and bond strengths are much higher. In the paper, two groups of corrugated steel-concrete composite structure specimens with the PUC were designed, and the positive and negative bending capacities of the composite structure specimens were tested by a symmetrical four-point loading test and compared with that of the composite structure specimens using the normal concrete. The test results show that the bending capacity and deformation property of the composite structure specimens with the PUC are greatly improved compared with those using the normal concrete. Compared with the positive and negative bending capacities of the corrugated steel-normal concrete composite structure specimens, the composite structure specimens using PUC in the compression zone increased by 137.88 % and 136.42 %, while the corrugated steel-PUC composite structure specimens increased by 311.69 % and 283.39 %. Since the PUC has high bond strength, the test results of the negative flexural rigidity of the corrugated steel-PUC composite structure specimens were evaluated higher than the derived theoretical results. The test results of the corrugated steel-normal concrete composite structure specimens and the composite structure specimens using PUC in the compression zone are consistent with the theoretical results. In addition, using the PUC in the compression zone greatly improves the negative bending performance of the composite structure.

Seismic Retrofit of Concrete Buildings Damaged by Corrosion: A Case Study in Southern Italy

A case study of a building in southern Italy, subjected to high degradation by corrosion and waiting to be assessed for retrofit interventions, is presented. The owner required modifications to the building configuration, including a new layout of the floors and retrofitting for a high level of seismic load. A double strategy of an assessment and retrofit was carried out: dynamic linear and static non-linear analyses were performed, and the results were compared. Afterwards, a global strategy of mass and stiffness redistribution was implemented together with different retrofit interventions on the foundations, columns, and beams of the framed structure, such as reinforced concrete and steel jacketing, the application of FRP plates and fabrics, new steel elements, and steel–concrete composite floors. The results of the intervention are discussed and the implications of corrosion on the structures are explored. From the results obtained, it is possible to see how the use of different techniques for strengthening and passive seismic protection strategy can allow engineers to obtain the result of structural adaptation to earthquakes with low-cost interventions. The widespread adoption of steel jackets, coupled with the construction of floors using a steel–concrete composite structure, grants a good confinement of the beam–column r.c. joints, together with the overall strengthening of the existing structure. The adoption of CFRP wrapping at the lower edge of the beams implies a limited increase in thickness and the limited interventions of partial demolition from the existing structural members. A critical review of the steel jacketing aspects in terms of bending and shear strengthening is reported by considering this technique in the form of a steel exoskeleton containing the damaged concrete structure, by confining concrete elements, and by increasing the performance for both gravitational and seismic loads.

Experimental study and acoustic emission monitoring on damage mechanism of stud shear connectors

Stud shear connectors are popular connectors used in steel-concrete composite structures. Assessing the condition and damage process of studs embedded in concrete is difficult. This paper proposes to assess the condition and damage process of stud shear connectors using an acoustic emission (AE) technique. Nine steel-concrete push-out specimens with stud shear connectors were tested, and AE sensors were used to monitor the damage process and explore the damage mechanism. The test results showed that the specimens failed due to stud fracture, accompanied by concrete cracks. The damage process included three primary stages featuring different characteristics of AE energy. An unsupervised machine learning algorithm called fuzzy C-means clustering was used to analyze the AE signals, and AE events were classified into three clusters, and various damage modes (i.e., concrete cracks and steel-concrete interface debonding, stud fracture, and concrete crushing) were identified based on the parameter characteristics and positions of AE events.

Fatigue growth behavior of mode II crack in headed stud steel used in steel–concrete composite structures

The fracture mechanics method has been employed for fatigue performance evaluation of stud used in steel–concrete composite structures while the fatigue crack growth behavior in headed stud steel has not been systematically studied. The present work is proposed to investigate the fatigue growth behavior of mode II crack in headed stud steel and its welded joint. Compact tensile shear (CTS) specimens extracted from the base material (BM) and weld metal (WM) of stud are tested under mode II loading to investigate the fatigue crack growth (FCG) trajectories and rates with different stress ratio. The crack closure level and FCG threshold are determined and discussed. Results show that the crack deflection in BM meets both the MTS criterion and S-criterion, while crack deflection in WM does not meet the two criterions. The 2% compliance offset criterion in the origin ASTM method is suitable to determine the crack opening force both for BM and WM of stud. The low crack closure level in WM indicates the tensile residual stress in welded joint, resulting a more quickly fatigue crack growth rate (FCGR) in WM than that in BM. The calculation formulation of equivalent SIF range proposed by Borrego et al. is verified with the best normalization effects and is recommended to fit the FCGR model both for headed stud steel and its welded joint under mode II loading.

Study of Innovative Connector for Steel–Concrete Composite Structures

The paper presents an analysis of the innovative connector for manufacturing a steel–concrete composite beam. The connector consists of a corrugated metal sheet in the shape of a dovetail and shot nails. The nails are shot through the sheet fold into the flange of the steel I-section. Experimental studies of push-out tests were carried out. The conducted tests proved that the proposed solution can be applied as the fastener for steel–concrete composite beams for the construction of ceilings in utility public buildings with small beam’s span. Considering the criteria presented in the Eurocode 4 standard and the results of the experiments, it was proven that all analyzed types of fasteners are ductile. The connector made of sheet with a thickness of 1.00 mm and 2 nails is characterized by a breaking load of 30.83 kN. The load-bearing capacity of the fastener can be adjusted by changing the corrugated sheet thickness and changing the number of nails shot in the single fold of the sheet.

Investigations on Blast Performance of Steel-Concrete Composite Structures

Blast performance of concrete and ultra-high performance fiber concrete (UHPFRC) has been subject to numerous publications in the past decades. The enhanced force-deflection diagram of fiber concrete and ultra-high performance fiber concrete provide massive increase on the protective function of these materials compared to regular concrete. Nevertheless, concrete spalling cannot be fully avoided even when using UHPFRC. The next step for harmful debris ejection prevention can be supplementing the concrete specimens with steel slabs. The steel slab will not just hold the debris, but can, if properly bonded with concrete, contribute to the load bearing capacity as steel-concrete composite structure. This paper presents an overview of recent experiments on blast resistance of steel-concrete composite slabs. In total 6 pairs of specimens (dimension 1.000/1.000/150mm) were prepared, 6 specimens using regular concrete and 6 specimens using UHPFRC. One pair of specimens was reinforced by a steel mesh at 30mm cover from the soffit, one pair was supplemented by a steel plate bonded with 4 studs in the corners, at the complementary specimen pair, the concrete was also covered with a steel plate at the side subjected to blast loading, in the case of the further pair of specimens, the steel plates were connected by steel bars arranged in a mesh 150/150mm. The final 2 pairs represented steel-concrete composite slabs, in the first case, the shear studs were supplemented with a steel mesh (according to provisions of the European standard for steel-concrete composite structures), in the last case, the shear studs were replaced by a shear plate. All specimens were subjected to the same contact blast loading. The paper presents the experimental arrangement, the achieved results and a brief discussion on the structural behavior.

Interfacial debonding detection for steel-concrete composite structures part I: Benchmark test and signal calibration of contact and non-contact measurement

Interfacial bonding state is one of the crucial factors affecting the bearing capacity and durability of steel-concrete composite structures (SCCS). To achieve efficient interfacial debonding detection for SCCS, contact and non-contact method-based novel non-destructive test (NDT) is performed in this study. In order to figure out the dominant frequency and vibration mode of steel plate above interfacial debonding defects in SCCS, systematic theoretical analysis and finite element simulation are carried out. Then, the contact NDT experimental study is carried out utilizing piezoelectric lead zirconate titanate (PZT) sensors and acceleration meters. Conventional and high-frequency microphones, as well as high-precision scanning laser Doppler vibrometer (SLDV), are introduced for non-contact measurement. According to benchmark test on steel plate-bonded reinforced concrete cube with preset interfacial debonding defects in different dimensions, the signal calibration with Pearson correlation coefficient is further performed to quantitatively assess the variation and difference between contact and non-contact measurements. Research findings indicate that the synthetic experimental testing platform integrating contact vibration measurement, non-contact SLDV, and acoustic vibration measurement established in this study is capable of performing non-destructive tests using impact-response method, impact-echo technique, impact-acoustic vibration approach, and modal test simultaneously. Moreover, SLDV can precisely obtain the vibration mode of steel plates above interfacial debondings. Aided by high-precision scanning laser-based vibration measurement, the accuracy and efficiency of in-situ non-contact tests can be improved. The research findings in this study can provide practical guidance on non-destructive evaluation of interfacial damages in SCCS.

Seismic performance and design of an innovative dual vertical diaphragms joint between flat CFST column and H-beam

Steel-concrete composite structure is one of the research hotspots in the structural engineering field in recent years. Among the various types of composite structures, flat concrete-filled steel tube (CFST) column structures are preferred for residential buildings owing to the smooth elevation to coordinate with the indoor decoration. The seismic performance of beam-to-column joints is momentous as a key part of flat CFST column structures. This study provided a new type of joint between flat CFST column and H-beam with dual vertical diaphragms through the column. The design procedure for the vertical diaphragms was proposed to design the test specimens. An experimental study on the seismic behavior of the innovative joint under cyclic load was performed on three full-scale specimens. The seismic performance of the joint, including the failure mode, hysteretic and skeleton curves, ductility and energy dissipation capacity, was observed and discussed in detail. Subsequently, nonlinear finite element models (FEMs), based on the specimens, were developed using the ABAQUS/Standard program and validated by comparing the numerical results with the test ones. The experimental and numerical results demonstrated that the proposed joint exhibited satisfactory seismic performance and all the specimens exhibited a ductile failure mode. The failure process and damage distribution of the joint under earthquake were revealed based on the validated FEM. Furthermore, a mechanical model was established to predict the load-bearing capacity of the shear force and bending moment of the proposed joint. The mechanical model was validated to be accurate and reliable by comparing the numerical simulation results with the theoretical ones. This study provided a practical joint between flat CFST column and H-beam as well as its design method, which was beneficial for the promotion of the flat CFST column structures.

Methodology for calculating load capacity reduction and slip relationship of clustered group nail connectors

Clustered group nail connectors are key connecting components for the full lifecycle construction and safe operation of steel–concrete composite structural bridges. To thoroughly investigate the stress mechanism of clustered group nail connectors in steel–concrete composite structures, this paper conducts a detailed numerical analysis on 100 sets of such connectors. It analyzes the stress mechanism of individual nail connectors and quantitatively calculates the group nail effect under the coupled action of multiple factors (nail spacing between layers, number of nail layers, concrete strength). Based on clarifying the force transmission patterns of nails and concrete in different layers during the loading process, this paper proposes a method for calculating the average bearing capacity reduction coefficient and the load-slip curve of single nails in clustered group nail connectors under the coupled action of multiple factors, which has been validated by experimental data. This research provides a theoretical basis for the design and calculation of group nail connectors in steel–concrete composite structural bridges.

Experimental study of concrete-filled stainless steel tubular stub columns with circular and square cross-sections subjected to combined compression and bending

This paper presents an experimental study into the structural behaviour and strength of concrete-filled stainless steel tubular stub columns with circular and square cross-sections subjected to combined compression and bending moment. A total of sixteen concrete-filled stainless steel tubular (CFSST) stub columns were tested, including two section types (circular and square hollow sections), two grades of concrete infill (C30 and C60), two thicknesses of tube wall for each cross-section (6 and 10 mm), and five loading eccentricity ratios (0, 0.2, 0.3, 0.4 and 0.5). The CFSST stub column specimens were loaded in compression, with different loading eccentricities applied to achieve a wide range of axial load-to-bending moment ratios. This research provides a comprehensive report on the experimental methodology and subsequent observations, including the failure modes, load-deformation curves, axial load-bending moment curves, strain development at the key locations and values of ductility index. It can be observed that for circular CFSST columns, ultimate load decreased by roughly 70% with an increase in loading eccentricity ratios from 0 to 0.5, while for square columns, the reduction was about 50% under same conditions. The experimental results were used to evaluate if the existing design provisions for carbon steel-concrete composite structures is capable of designing the investigated CFSST stub columns. It was found that the mean ultimate load to predicted failure load ratios are 1.25, 1.32, and 1.36, with coefficients of variations (COV) equal to 0.08, 0.09 and 0.11, for the European, American, and Chinese codes, respectively. Consequently, the design approach specified in the Chinese code led to the most conservative and scattered strength predictions among the three codified design approaches. In contrast, the European code provides the most precise predictions of the test results, though there still remains scope for improvements in the ultimate resistance predictions of CFSST stub columns subjected to combined compression and bending.

Shear performance of high-strength bolt-epoxy bonding composite connector in steel-concrete composite structure

To clarify the shear mechanism of high-strength bolt-epoxy bonding composite connectors in prefabricated steel-concrete composite structures, twenty-one direct shear specimens and six double shear specimens were carried out in this study. The pretension force, interface type, epoxy curing time and loading pattern were considered. Results revealed that the main failure mode of high-strength bolt-epoxy bonding composite connectors was that the large area of epoxy matrix was separated from the steel plate, and the bolt was sheared off. The load-slip curve of composite connector specimens included the elastic stage, epoxy failure stage, frictional slip stage, bolt force transmission stage and failure stage. Compared to the specimens with a bolt connector under recommended pretension, the average initial slip load of composite connector specimens was 437.7% higher. Additionally, the average initial slip load of specimens with 1-day epoxy curing time was 24.4% lower than 7-day curing time, but the average ultimate load and ultimate slip were 12.4% and 29.4% higher, respectively. When the pretension ratio decreased from 1.0 to 0.6, the average initial slip load of specimens with a bolt connector was significantly decreased by 33.0% and the average ultimate slip of composite connector specimens was increased by 18.1%. The average initial slip load and ultimate load of composite connector specimens were comparable under cyclic loading compared to monotonic loading. Upon the experimental results and existing formulas, some equations were proposed for predicting the initial slip load and bearing capacity of steel-concrete composite structures with composite connectors.

Design method of irregular-shaped concrete-filled steel tube column joints with inner semi-diaphragm

This paper studies the mechanical behavior and design method of the irregular-shaped concrete-filled steel tube column to H-shaped steel beam joints with inner semi-diaphragm (ICFSTC-Joint) by numerical and theoretical investigation. ICFSTC-Joint was proposed and tested in the authors’ previous paper, which can be adopted in steel-concrete composite structures. Firstly, the tensile and compressive bearing capacity of ICFSTC-Joint under the tension or compression of a single beam flange is investigated. Secondly, based on the tensile and compressive bearing capacity, the bending capacity of the ICFSTC-Joint under the bending exerted by a complete H-shaped beam is investigated. Finally, the interaction between multiple ICFSTC-Joints is considered. The FE model verified by the hysteretic experiment of ICFSTC-Joint is adopted in the parameter analysis. The parameter analysis involves the height of beam, width and thickness of beam flange, height and thickness of diaphragm, thickness of column wall, length of column limb and axial compressive ratio. Based on the parameter analysis results, the mechanical models of ICFSTC-Joint under various conditions are established. The complete set of design method as well as some constructional requirements are finally established through the theoretical derivation of mechanical models and fitting the FE investigation results and exhibit good precision.

Effective width of steel-concrete composite box girder bridges: a review and method comparison

Steel-concrete composite girders have non-uniform stress distribution on the slab, presenting maximum stresses next to the webs of the girder. This phenomenon is known as shear lag effect. To understand this effect, there is the effective width concept, in which only a portion of the slab width is considered effective in contributing to the composite element’s resistant capacity. However, in the technical standards, there is no recommendation for calculating the effective width in steel-concrete composite box girder bridges. In view of this situation, the purpose of this paper is to carry out a systematic review on effective width and/or the shear lag effect in steel-concrete composite bridges, in order to raise the main existing recommendations and compare them. Through a bibliometric scan with carefully chosen keywords, it was found that of all research on shear lag or effective width in steel-concrete composite structures, only 31.19 are on bridges and 14.97% are on bridges with box girders. Among the papers, those that have a method for calculating the effective width of steel-concrete composite girder bridges have been compared quantitatively and qualitatively with the procedures of AASHTO and EN 1994-2-2. In these procedures were also identified that the, for the boundary conditions of the present paper, the parameters that most influencing the effective width are, in that order, the span length, the distance between girders, the concrete slab height, the longitudinal position and the type of load.

Study on the protection mechanism and damage grade prediction of different corrugated steel‒concrete composite structures under underwater contact explosion

Considering that corrugated steel has a certain anti-explosion protective effect, the influences of corrugated steel shape parameters on the protective effect of corrugated steel–concrete composite structures have not been considered. In this paper, the FEM–SPH coupling method is used to establish a simulation model of an underwater contact explosion wall panel. The numerical results are compared with the experimental results to verify the effectiveness of the simulation method. Furthermore, the underwater energy absorption effect, protection effect and influences of the wall panel of different composite structure protective layers on the damage process and failure mode are explored, the underwater explosion-proof mechanism is revealed, and the prediction curve of the damage grade of the wall panel is constructed. The results show that simulation results of the concrete slab front and back explosion surfaces are basically consistent with the experimental results. Under different composite structure protection schemes, the peak pressures of the composite structure protection schemes with 12-mm-thick corrugated steel and with 75° corrugated steel are reduce by 63.2% and 60%, respectively, relative to the noncomposite protection scheme, while the total energies of the corresponding composite structure are increased by 50.6% and 61.4%, respectively; the damage ranges of the wall panel are reduced by 83% and 81.6%, respectively. This finding shows that changing the corrugated steel shape parameters in the composite structure can effectively improve the energy absorption effect and reduce damage to the wall panel. The blast wave first propagates to the corrugated steel in the form of an incident wave and then propagates in the form of transmitted and reflected waves. Part of the wave propagates to the wall panel when the transmitted wave arrives at the corrugated steel lower surface, while the rest of the wave forms a reflected longitudinal wave and reflected transverse wave through reflection. Then, the transmitted wave acting on the wall panel attenuates. Under the protection schemes of the corrugated steel composite structure with a 12-mm thickness and corrugated steel composite structure with a 75° angle, the maximum protection rates are 63.2% and 60.0%, respectively, the energy consumption sharing rates are 69.48% and 66.26%, respectively, and the damage levels are moderate. The multiangle comparative analyses of different protection schemes suggest that the corrugated steel composite structure with a 12-mm thickness should be selected. The prediction curve can intuitively evaluate the influences of the quantity of explosive loads and the thickness/angle of corrugated steel changes of the composite structure on the damage to the wall panel. The research results can serve as a reference for the adhibition of underwater explosion protective engineering projects.

Analysis of stress mechanism in a new prefabricated SRC composite column

The superior seismic performance of prefabricated steel-concrete composite structures has recently become a major research focus in the earthquake engineering field. This study proposes an off-site precast steel reinforced concrete (PSRC) column base joint. This joint has a high bearing capacity, efficient assembly, and a fuse function for plastic deformation accumulation at the middle connection. Besides, multiple finite element models are built and calibrated based on the test results using ABAQUS. The research discusses the influence of various parameters on failure modes and seismic performance. The results indicated that the failure position is primarily concentrated in the middle connection, whereas the stress distribution differs within the middle connection. The axial compression ratio and the middle connection position height significantly affect the initial stiffness. The bearing capacity is considerably influenced by various parameters, excluding the thickness of the stiffening plate and cover plate. It is recommended to use an optimal axial compression ratio of 0.45 and a shear span ratio between 2.0 and 2.8 while controlling the stiffening and cover plate thicknesses between 10 and 16 mm. The shear mechanism of the PSRC column base joint mainly includes a steel plate shear wall mechanism and a T-shaped steel frame mechanism. The simplified bearing capacity model results for the proposed PSRC column base joint match well with the experimental and FEM results, and the calculation results are good.

Reconstruct the 3D load redistribution paths of framed structures subjected to local column failure and multi-floor fire

Considering the slabs in the global response of steel framed buildings in fires is important, as deflected floor slabs could redistribute the load to columns leading to column failure and even progressive collapses. Floor slab systems also experience tensile membrane action after deflection, which differs from the behaviour observed using 2D structural fire models. This paper focuses on unfolding the load redistribution mechanisms using 3D steel-concrete composite structure models, while multi-floor spreading fires and local failure of columns are considered. A framed structural model based on the Cardington building is designed and modelled, in which the composite slabs at different floors are simulated using the recently developed high-efficiency slab model to address the slab effect to the global load redistribution. Four hazard scenarios representing different states of the central column (i.e., fully protected, partially protected or failed) are given as the initiating local failure. The analyses with the 3D structural models show that the slabs can effectively pull up the failed column and the vertical loads are transferred to the adjacent columns. The worst scenario has been identified as the case experiencing column failure both at the upper floor and the lower floor, which leads to the middle floor without pulling action and causes significantly large deflection. This may be a scenario that local column failure triggers progressive collapse of a real building and should be prevented.

Collapse Resistance of Composite Structures with Various Optimized Beam–Column Connection Forms

Steel–concrete composite structures are widely used in composite frame structures and super high-rise buildings. However, the lack of relevant building design standards to ensure their structural stability under extreme conditions has led to potential failures in beam–column connections due to excessive loads. These failures can trigger the progressive collapse of high-rise buildings, resulting in severe casualties. In this study, a comparative numerical analysis was conducted to evaluate the collapse resistance of composite structures in the event of a middle-column loss scenario, focusing on six commonly used beam–column connections. The results show that while the six connections exhibit minimal differences under normal operating conditions, they display significant variations when subjected to extreme loads. Furthermore, a design concept is proposed to enhance the collapse capacity of these structures, and its effectiveness is validated via analysis.

Bolted shear connectors in steel–concrete composite structures: Shear behavior

The use of bolted shear connectors is of great importance to the sustainable development of steel–concrete composite structures. In this paper, an experimental program consisting of four push-out specimens is performed to investigate the effects of bolt length and fabrication method of concrete slabs on the shear behavior of single-nut embedded bolted shear connectors in terms of failure mode and load-slip response. The concrete slabs are fabricated either as cast-in-situ monolithic slabs or precast slabs with reserved pockets which will be filled with grout in the final construction stage. The obtained results demonstrate that the fabrication method based on grouting, which is commonly utilized for strengthening and retrofitting works, does not affect the behavior of the bolted shear connection. Based on the experimental observations, a finite element (FE) model of the bolted shear connection is developed, after the obtained numerical results are verified against the test results obtained in this paper and those presented in other existing literature, a parametric study is carried out to further investigate the effects of the concrete strength, bolt strength, bolt diameter, bolt pretension load, and the length-to-diameter ratio of bolt on the performance of the bolted shear connection. Moreover, based on the obtained results, a design formula is proposed to obtain the ultimate shear resistance of the bolted shear connection, and the efficacy of the proposed design formula is proved through the comparison with the test results shown in the existing literature.