• Journal of Korean Society of Steel Construction
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• v.28 no.1
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• pp.53-64
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• 2016

The double split tee connection, a type of beam-to-column moment connection, exhibits different behavioral characteristics according to changes in the thickness of the T-stub flange, the gauge distance of the high-strength bolt, and the number and diameter of high-strength bolts. In general, the double split tee connection is idealized and designed so that a T-stub fastened to the top and bottom supports a flexural moment, and a shear tab supports a shear force. However, if the double split tee connection is applied to low-and medium-rise steel structures, the size of the beam member becomes small, and thus the shear tab cannot be bolted to the web of a beam. In this regard, this study was conducted to propose connection details to ensure that the double split tee connection with a geometric shape can display sufficient shear resisting capacity. To this end, experiments were conducted using full-scale specimens for the double split tee connection.

• Steel and Composite Structures
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• v.2 no.5
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• pp.315-330
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• 2002

This paper proposes a model for analysing the non-linear behaviour of steel concrete composite beams prestressed by external slipping cables, taking into account the deformability of the interface shear connection. By assuming a suitable admissible displacement field for the composite beam, the balance condition is obtained by the virtual work principle. The solution is numerically achieved by approximating the unknown displacement functions as series of shape functions according to the Ritz method. The model is applied to real cases by showing the consequences of different connection levels between the concrete slab and the steel beam. Particular attention is focused on the limited ductility of the shear connection that may be the cause of premature failure of the composite girder.

• Steel and Composite Structures
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• v.16 no.6
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• pp.611-637
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• 2014

A single plate shear connection, or shear tab, is a very popular shear connection due to its merit in ease of construction and material economy. However, problems in understanding the connection behavior, both in terms of strength and ductility, have been well-documented. Suggestions or design model for single plate connections in AISC Design Manual have been altered several times, with the latest edition settling down to giving designers pre-calculated design strength tables if the connection details agree with given configurations. Results from many full-scale tests and finite element models in the past suggest that shear strength of a bolt group in single plate shear connections might be affected by yield strength of plate material; therefore, this research was aimed to investigate and clarify effects of plate yield strength and thickness on shear strength of the bolt group in the connections, including the validity of using a plate thickness/bolt diameter ratio ($t_p/d_b$) in design, by using finite element models. More than 20 models have been created by using ABAQUS program with 19.0- and 22.2-mm A325N bolts and A36 and Gr.50 plates with various thicknesses. Results demonstrated that increase of plate thickness or plate yield strength, with the $t_p/d_b$ ratio remained intact, could significantly reduce shear strength of the bolt group in the connection as much as 15 percent. Results also confirmed that the $t_p/d_b$ ratio is a valid indicator to be used for guaranteeing strength sufficiency. Because the actual ratio recommended by AISC Design Manual is $t_p/d_b$ + 1.6 (mm) for connections with a number of bolts less than six and plate yield strength in construction is normally higher than the nominal value used in design, it is proposed that shear strength of a bolt group in single plate connections with a number of bolts equal or greater than seven be reduced by 15 percent and the $t_p/d_b$ ratio be limited to 0.500.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.685-695
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• 2020

The connection performance between cross-laminated timber (CLT) walls and support has the greatest effect on the horizontal shear strength. In this study, the horizontal shear performance of CLT walls with reinforced connection systems was evaluated. The reinforcements of metal bracket connections in the CLT connection system was made by attaching glass fiber-based reinforcement to the connection zone of a CLT core lamina. Three types of glass fiber-based reinforcement were used: glass fiber sheet (GS), glass fiber cloth (GT) and fiber cloth plastic (GTS). The horizontal shear strength of the fabricated wall specimens was compared and evaluated through monotonic and cyclic tests. The test results showed that the resistance performance of the reinforced CLT walls to a horizontal load based on a monotonic test did not improve significantly. The residual and yield strengths under the cyclic loading test were 38 and 18% higher, respectively, while the ductility ratio was 38% higher than that of the unreinforced CLT wall. The glass fiber-based reinforcement of the CLT connection showed the possibility of improving the horizontal shear strength performance under a cyclic load, and presented the research direction for the application of real-scale CLT walls.

• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.623-634
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• 2013

In this study, the structure behavior of RC slab and SC shear wall connection was investigated. Also experimental study was performed to evaluate the factor of safety of demand shear connection strength in KEPIC SNG Standard. As a result, shear friction strength of connection was known about 300kN and shear strength of rebar increased according to the displacement increase. With the installment of the lower rebars, 40% shear strength increased compared to the non-rebar specimen.

• Architectural research
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• v.7 no.1
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• pp.27-38
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• 2005

No specific guidelines are available for computing the bearing strength of connection between steel coupling beam and reinforced concrete shear wall in a hybrid wall system. There were carried out analytical and experimental studies on connection between steel coupling beam and concrete shear wall in a hybrid wall system. The bearing stress at failure in the concrete below the embedded steel coupling beam section is related to the concrete compressive strength and the ratio of the width of the embedded steel coupling beam section to the thickness of the shear walls. Experiments were carried out to determine the factors influencing the bearing strength of the connection between steel coupling beam and reinforced concrete shear wall. The test variables included the reinforcement details that confer a ductile behavior in connection between steel coupling beam and shear wall, i.e., the auxiliary stud bolts attached to the steel beam flanges and the transverse ties at the top and the bottom steel beam flanges. In addition, additional test were conducted to verify the strength equations of the connection between steel coupling beam and reinforced concrete shear wall. The proposed equations in this study were in good agreement with both our test results and other test data from the literature.

• Steel and Composite Structures
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• v.31 no.1
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• pp.53-67
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• 2019

This study presents finite element analysis (FEA) on a Y-type perfobond rib shear connection using Abaqus software. The performance of a shear connection is evaluated by conducting a push-out test. However, in practice, it is inefficient to verify the performance by conducting a push-out test with regard to all design variables pertaining to a shear connector. To overcome this problem, FEA is conducted on various shear connectors to accurately estimate the shear strength of the Y-type perfobond rib shear connection. Previous push-out test results for 14 typical push-out test specimens and those obtained through FEA are compared to analyze the shear behavior including consideration of the design variables. The results show that the developed finite element model successfully reflects the effects of changes in the design variables. In addition, using the developed FEA model, the shear resistance of a stubby Y-type perfobond rib shear connector is evaluated based on the concrete strength and transverse rebar size variables. Then, the existing shear resistance formula is upgraded based on the FEA results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.229-239
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• 2010

For the purpose of improvement of the load carrying capacity and constructibility of the conventional steel-concrete composite girder through a effective appliance of the construction materials and optimization of the girder section, a new type section of composite girder and RC shear connection were proposed. In this study shear strength of the RC shear connection is estimated, and the characteristics of shear load-slip behaviour is analyzed. Push-out tests on shear specimens and FEM analysis with various design parameters are carried out, and results are analyzed. The results of test and FEM analysis showed that shear strength of RC shear connection is underestimated by the design provisions of the current design code. By regression analysis a empirical equation for the estimation of shear strength of RC shear connection is proposed.

• Steel and Composite Structures
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• v.28 no.4
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• pp.449-460
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• 2018

This paper reports the experimental results of three through bolt beam-column connections under pure shear forces using modified push-out tests. The investigated specimens include extended end-plates and six through-bolts connecting square concrete-filled steel tubular column (S-CFST) to steel beams. The main goal of this study is to investigate if and how the mechanical shear connectors, such as steel angles and stud bolts, contribute to the shear transfer mechanisms in the steel-concrete interface of the composite column. The contribution of shear studs and steel angles to improve the shear resistance of steel-concrete interface in through-bolt connections was investigated using tests. The results showed that their contribution is not significant when the beam-column connection is included in the push-out tests. The specimens failed by pure shear of the long bolts, and the ultimate load can be predicted using the shear resistance of the bolts under shear forces. The predicted values of load allowed obtaining a good agreement with the tests results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5566-5571
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• 2012

Block shear failure is one of limit states, and demands great caution in designing the tension member or connection joint of steel structures. From many studies and design specification, it is shown that the effect of the bolted connection type on the block shear failure was not considered. In order to investigate the effect of the bolted connection type(bearing type connection and slip critical connection) on the mode/strength of the block shear failure, tensile experiment is conducted in this study. Differences about the failure mode according to the design specification, bearing type connection, and slip critical connection are proposed from the analysis of test results. The variation of the block shear failure strength due to the frictional force in the slip critical connection is also investigated.