• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.4
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• pp.61-71
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• 2010

Five half-scale beam-to-column connections in a precast concrete frame were tested with cyclic loading that simulated earthquake-type motions. Five half -scale interior beam-column assemblies representing a portion of a frame subjected to simulated seismic loading were tested, including one monolithic specimen and four precast specimens. Variables included the detailing used at the joint to achieve a structural continuity of the beam reinforcement, and the type of special reinforcement in the connection (whether ECC or transverse reinforcement). The specimen design followed the strong-column-weak-beam concept. The beam reinforcement was purposely designed and detailed to develop plastic hinges at the beam and to impose large inelastic shear force demands into the joint. The joint performance was evaluated on the basis of connection strength, stiffness, energy dissipation, and drift capacity. From the test results, the plastic hinges at the beam controlled the specimen failure. In general, the performance of the beam-to-column connections was satisfactory. The joint strength was 1.15 times of that expected for monolithic reinforced concrete construction. The specimen behavior was ductile due to tensile deformability by ECC and the yielding steel plate, while the strength was nearly constant up to a drift of 3.5 percent.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.2
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• pp.209-218
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• 2003

The analytical studies included nonlinear finite element analysis of split-tee connection details subjected to axial load and lateral load. A three-dimensional model of the connections between CFT columns and H-beams has been developed. Both initial geometrical imperfections and residual stresses are taken into consideration. A geometrically nonlinear load-displacement analysis of the structure containing the imperfection is then performed, using the Riks method. Analytical results are compared with existing experimental results. Extensive parametric analyses are carried out to investigate the relation of the connections between CFT columns and H-beam to various parameters such as the axial load, column width-thickness ratio, and split-tee thickness.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.789-799
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• 1998

The purpose of this study is to propose the prototypes of bolted end plate moment connection between CFT column and H-beam sections. Nine different types of bolt are designed in this study. The shapes of those bolt are straight. bent, hooked or stud-type. The end plate moment connection between CFT column and H-beam sections which are jointed by those bolts are studied experimentally to compare their performances. The simple beam bending tests are carried out to investigate the structural behavior of beam-to-column connections. The experimental results show that some of the bolted end plate connection types have quite good performance in the structural behavior but still have a lot of week points to be solved for the efficiency of construction.

• Structural Engineering and Mechanics
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• v.24 no.3
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• pp.307-321
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• 2006

This paper is concerned with the behaviour of steel and concrete composite joints subjected to reversal of loading. Three cruciform composite joint specimens and one bare steel joint specimen were tested so that one side of the beam-to-column connection was under negative moment and another side under positive moment. The steelwork beam-to-column connections were made of bolted end plate with an extended haunch section. Composite slabs employing metal decking were used for all the composite joint specimens. The moment-rotation relationships for the joints were obtained experimentally. Details of the experimental observations and results were reported.

• Steel and Composite Structures
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• v.52 no.1
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• pp.109-119
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• 2024

This study presents a replaceable reduced beam section (R-RBS) located at the column end in moment resisting frames (MRFs). An end of the R-RBS is connected to column by using end-plate moment connection and the other end of that is connected to main beam with beam splice connection. Therefore, the RBS that is expected to yield under an earthquake can be easily replaceable. Geometry of the RBS and the thickness of the beam splice connection are the prime variables of this study. A total of eight experimental test was carried out to examine the seismic performance of the proposed R-RBS with the connection details. The results obtained from experimental studies demonstrated that plate sizes of the beam splice connection significantly affect the seismic performance of RBSs used in MRFs.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.10a
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• pp.230-238
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• 1996

Recently, square hollow section (S.H.S) is frequently used for column and H-section for beam of steel building structures. The connection between S.H.S column and H-beam is found to weaken the rotational restraint of the joint. Several types of detail to overcome the problem have been suggested for the connection between concrete filled S.H.S column and concrete composited H-bean In this paper, modelling technique to monitor the behavior of the connections is proposed. Then, Drucker-Prager yield criteria is introduced to simulate yield behavior of in-fill concrete while Von-Mises was used in earlier works. Gap-elements are also introduced to simulate the interaction between S.H.S columns and the in-fill concrete as in privious papers. axial forces are applied to S.H.S columns and made to vary in intensity and eccentricity.

• Journal of Korean Society of Steel Construction
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• v.11 no.3 s.40
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• pp.271-279
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• 1999

Recently, studies on semi-rigid beam-to-column connections have been done to develop a T-stub element with separators between column face and T-stub flange. In this paper, inelastic analyses for the improved T-stub element are performed, and their results are compared with existing experimental results. The inelastic analyses using gap elements between column face and the separator, and initial stresses at the high-tension bolts result in good agreement with experimental results. Simplified design methods estimating the initial stiffness and the strength of the semi-rigid connection for compression force are proposed.

• Journal of Korean Society of Steel Construction
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• v.23 no.6
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• pp.737-745
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• 2011

A concrete-filled tube is a concrete-filled steel tube structure. The steel tube confines the concrete to increase the compressive strength, and the concrete contains the buckling of the tube. CFT structures require a diaphragm to prevent buckling of steel at connections. An outer diaphragm has better concrete filling than a through diaphragm due to a large bore, but being larger than the through diagram, it has poorer constructability and cooperation with building equipment. In this study, a CFT structure that uses different types of diaphragms in its upper and lower connections to improve the concrete filling was tested and analyzed via the FEM program. The building structure had a floor slab that was unified with the upper diaphragm, so the outer diaphragm was placed at the upper bound. Moreover, the through diaphragm was placed at the lower connection to avoid obstruction from building equipment. The CFT structure with the improved concrete filling showed the same structural behavior as the CFT structure with the use of the same type of diaphragms at the upper and lower connections.

• Journal of Korean Society of Steel Construction
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• v.28 no.2
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• pp.75-83
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• 2016

Existing tubes for concrete filled tubular structure are made through welding of four plates irrespective, but the production performance is poor and special welding technique is needed to weld the internal or through diaphragm. Accordingly, We developed a welded built-up square steel tube having a welding lines and a stiffeners at location out of stress concentration. The welded built-up square steel tube occurred a interference with stiffeners at the internal or through diaphragm, therefore researches of a external diaphragm for welded built-up square CFT column connections are needed for the purpose of avoidance of a interfere with stiffeners. In this study we suggest a design formulation for external diaphragm of the welded built-up square CFT external diaphragm connections. Four specimens were manufactured for a experimental test, then we analyzed the behaviors of the specimens.

• Journal of Korean Society of Steel Construction
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• v.27 no.3
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• pp.311-321
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• 2015

In this study, an experimental study to evaluate the seismic performance of beam-to-column connection for medium and low-rise building was conducted. Five connections using SHN490 steel were made with test variables such as flange welded or bolted, web welded or bolted. Specimen SHN-W-W is web welded and flange welded type. Specimen SHN-W-B is web welded and flange bolted type. Specimen SHN-B-W is web bolted and flange welded type. Specimen SHN-B-B is web bolted and flange bolted type. Specimen SHN-EP is a connection with the end plate to the beam ends. Cyclic loadings was applied at the tip of beam following KBC2009 load protocol. The load vs rotation curves for different connection are shown and final failure mode shapes are summarized. The connections are classified in terms of stiffness and strength as semi-rigid or rigid connection. Energy dissipation capacities for seismic performance evaluation were compared.