• Steel and Composite Structures
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• v.32 no.1
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• pp.111-126
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• 2019

This paper deals with experimental investigation and modeling of the static behavior of a novel RCS beam-column exterior joint. The studied joint detail is a through-column type in which an H steel profile totally embedded inside RC column is directly welded to the steel beam. The H steel profile was covered by two supplementary plates in the joint area in order to avoid the stirrups resisting shear in the joint area. Two full-scale through-column-type RCS joints were tested under static loading. The objectives of the tests were to examine the connection performance and to highlight the contribution of two supplementary plates on the shear resistance of the joint. A reliable nonlinear 3D finite element model was developed using ABAQUS software to predict the response and behavior of the studied RCS joint. An extensive parametric study was performed to investigate the influences of the stirrups, the encased profile length and supplementary plate length on the behavior of the studied RCS joint.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.977-982
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• 2000

As a newly structural system, RCS composite system has been researched last two decades. However mechanism of exterior T-type joint for RCS composite system is not well known. This research is focus on the exterior T-type joint for RCS composite system. Specimens are designed by the ASCE guideline, tested and compared with the inner RCS joint. Test variables include face bearing plate(FBP), extended face bearing plate(E-FBP) and U-bar. The tests indicate that the strength of exterior T-type joint is higher than that of the guideline by ASCE. The U-bar has a significant effect on the joint strength and absorbing the strain energy.

• Earthquakes and Structures
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• v.18 no.5
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• pp.599-607
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• 2020

This paper deals with the experimental investigation on the behavior of RCS beam-column exterior joints. Two full-scale specimens of joints between reinforced concrete columns and steel beams are tested under cyclic loading. The objective of the test is to study the effect of steel fiber reinforced concrete (SFRC) on the seismic behavior of RCS joints. The load bearing capacity, story drift capacity, ductility, energy dissipation, and stiffness degradation of specimens are evaluated. The experimental results point out that the FRC joint is increased 20% of load carrying capacity and 30% of energy dissipation capacity in comparison with the RC joint. Besides, the FRC joint shown lower damage and better ductility than RC joint.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.139-146
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• 2001

Res system, with Reinforced Concrete columns and Steel beams, is defined as system in which both steel and concrete materials are efficiently combined to maximize the structural and economic advantages of each material. Tested in this study were 4 exterior beam-to-column joint specimens with variables that influence joint rigidity of RCS structure. The purpose of this study is to compare and analyze the structural behavior of exterior joints through the existing studies and tests, and offer basic data for practical use of RCS structure by studying flexible behavior(semi-rigid effect) of joints according to joint details.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.4
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• pp.1-9
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• 2015

This study is on the shear strength of the internal joints of RCS composite structure consisting of reinforced concrete column and steel beam. As a newly structure system, the composite system has been developed to fully utilize the advantages of reinforced concrete column and steel beam, which also include economic and practical joint detail. Nevertheless stress transfer mechanism and structural behavior of the joints had not been still clearly revealed and shown much difference from the proposed equation. In this study, by observing the crossing of reinforced concrete column through steel beam to the RCS structure beam type, thirty seven shear failure specimens were selected and applied to the 5 major equations which is used to calculate the shear strength of RCS joint. Through the regression analysis, modified equation which is more reliable and approximate results for shear strength of RCS joints was proposed.

• Steel and Composite Structures
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• v.18 no.4
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• pp.971-983
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• 2015

To promote greater acceptance and use of composite RCS systems, a two-bay two-story frame specimen with improved composite RCS joint details was tested in the laboratory under reversed cyclic loading. The test revealed superior seismic performance with stable load versus story drift response and excellent deformation capacity for an inter-story drift ratio up to 1/25. It was found that the failure process of the frame meets the strong-column weak-beam criterion. Furthermore, cracking inter-story drift ratio and ultimate inter-story drift ratio both satisfy the limitation prescribed by the design code. Additionally, inter-story drift ratios at yielding and peak load stage provide reference data for Performance-Based Seismic Design (PBSD) approaches for composite RCS frames. An advantage over conventional reinforced concrete and steel moment frame systems is that the displacement ductility coefficient of the RCS frame system is much larger. To conclude, the test results prove that composite RCS frame systems perform satisfactorily under simulated earthquake action, which further validates the reliability of this innovative system. Based on the test result, some suggestions are presented for the design of composite RCS frame systems.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.297-304
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• 2003

This paper presents the test results of RCS(Reinforced Concrete Steel) beam-column joint with various types of transverse reinforcements such as small-column-type transverse reinforcements, four-piece ㄱ-shape assembled hoops and four-piece ㄱ-shape welded hoops. Five interior beam-column joint specimens were tested to examine the seismic performance and the shear strengths. From the test results, it was found that all the specimens sustained their strength at large levels of story drift(${\theta}$=0.035) without significant loss of strength and stiffness. Therefore it was concluded that the seismic performance and shear strength of the proposed RCS joint are at least the same as those of the specimen with conventional reinforcing details. Also, the contribution of the outer panel to the shear strength of the joint should be evaluated by the compression strut mechanism rather than compression field mechanism.

• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.417-430
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• 2023

As the key part in the reinforced concrete column-steel beam (RCS) frame, the beam-column joints are usually subjected the axial force, shear force and bending moment under seismic actions. With the aim to study the seismic behavior of RCS joints with and without RC slab, the quasi-static cyclic tests results, including hysteretic curves, slab crack development, failure mode, strain distributions, etc. were discussed in detail. It is shown that the composite action between steel beam and RC slab can significantly enhance the initial stiffness and loading capacity, but lead to a changing of the failure mode from beam flexural failure to the joint shear failure. Based on the analysis of shear failure mechanism, the calculation formula accounting for the influence of RC slab was proposed to estimate shear strength of RCS joint. In addition, the finite element model (FEM) was developed by ABAQUS and a series of parametric analysis model with RC slab was conducted to investigate the influence of the face plates thickness, slab reinforcement diameter, beam web strength and inner concrete strength on the shear strength of joints. Finally, the proposed formula in this paper is verified by the experiment and FEM parametric analysis results.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.417-424
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• 2003

A bearing failure in RCS(Reinforced Concrete Column and Steel Beam) system is recognized as one of the distinct joint failure modes for the composite frames. Vertical and transverse reinforcement in addition to concrete are effective for better transfer of vortical forces through concrete bearing. To examine the effect of the vertical bars, tie bars, a U-type detail developed in this study and concrete confinement, local bearing tests were conducted using 22 small-scale concrete block specimens. Test results show that vertical reinforcement and tie bars mainly contribute to the bearing capacity. However larger amounts of tie reinforcement are required than those recommend from ASCE guidelines, to apply the nominal concrete strength as 2 $f_{ck}$ over the bearing area. Cross ties are proved to be highly effective for resisting the vertical forces. Maximum bearing strength can be increased upto 2.5 $f_{ck}$ . An accurate prediction model for bearing strength is proposed for better design of the composite Joint.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.577-581
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• 1998

Recent trends in the construction of building frame feature the increase use of composite steel concrete members functioning together in what terms of mixed structural systems. One of such systems, RCS(reinforced concrete column and steel beam) system, is known to make use of type of member in the most efficient manner to maximize the structural and economic benifits. Based on the results, joint behavior and design were described in terms of two primary modes of failure ; joint panel shear and vertical bearing. In test specimen, joint deformation is observed at internal region greater than at external region.