• Journal of Korean Society of Steel Construction
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• v.24 no.2
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• pp.199-206
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• 2012

Unstiffened seated connections (USC) ensure easy installation and safety during erection, thereby making the process more economical. USCs consist of a seat angle for carrying the beam's reactions and a top angle to provide beam stability. These angles are bolted or welded to the beam and supporting member. This paper sought to propose a design table for the weld strength of such connections obtained from the elastic vector method (EVM) and the instantaneous center-of-rotation method (ICM) in terms of calculating the eccentricity. Also, the proposed design table is compared with both AISC and KBC specifications.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.34-41
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• 2006

A 3-dimensional stress measurement system based on the bore hole bottom deformation method, which is one of the stress relief methods, was developed. A pilot bore hole is drilled from the bottom of a bore hole and the stress meter is inserted into the pilot bore hole in the method. The bore hole is advanced as an over coring and the deformations in seven directions are measured by cantilever type-sensors. Using the cantilever type-sensors saves time for hardening of glue. No cable connection between the stress meter and a data logger is necessary since a compact data logger is installed in the stress meter. The accuracy of the stress meter was confirmed by a biaxial test for a Shikotsu welded tuff block although in-situ tests have not been carried out yet.

• Steel and Composite Structures
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• v.1 no.3
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• pp.329-340
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• 2001

Cyclic response of "shear" connections between steel outrigger beams and reinforced concrete core walls is presented in this paper. The connections investigated in this paper consisted of a shear tab welded onto a plate that was connected to the core walls through multiple headed studs. The experimental data from six specimens point to a capacity larger than the design value. However, the mode of failure was through pullout of the embedded plate, or fracture of the weld between the studs and plate. Such brittle modes of failure need to be avoided through proper design. A capacity design method based on dissipating the input energy through yielding and fracture of the shear tab was developed. This approach requires a good understanding of the expected capacity of headed studs under combined gravity shear and cyclic axial load (tension and compression). A model was developed and verified against test results from six specimens. A specimen designed based on the proposed design methodology performed very well, and the connection did not fail until shear tab fractured after extensive yielding. The proposed design method is recommended for design of outrigger beam-wall connections.

• Journal of Korean Society of Steel Construction
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• v.14 no.1
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• pp.121-130
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• 2002

This paper presents the tensile behavior of a Concrete-Filled Square Steel Tubular (CFT) column to H-beam welded connections. These connections were externally reinforced with T-shaped stiffeners at the junction of CFT column and beam. The tensile loading tests of eighteen tee-joint connections and finite element analysis using ANSYS were carried out. The main parameters of tests are as follows: 1) the thickness of Square Steel Tubular Column : 6 mm, 9 mm, 2) the strength ratios of tensile strength of horizontal stiffeners to tensile strength of beam flange : 70 %, 100 %, 150 %, 3) the strength ratios of shear strength of vertical stiffeners to tensile strength of beam flange : 80 %, 115 %, 160 %. The results of the tests demonstrate that overall behavior and failure modes of all the specimens are governed mainly by the horizontal stiffeners rather than the vertical stiffeners, and the vertical stiffener played only a role in transferring load introduced from beam to column.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.611-623
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• 1997

This paper provides the results of an experimental and analytical study performed on the beam to Concrete Filled Circular Steel Column connections with the external stiffener rings under the gravity loads. Specimens are modeled as a 1/4 scale of the beam-columns as gravity loads are applied to a multi-story frame. Important parameters in this study are the width of the external rings, the diameter-thickness ratios of column and whether or not the external rings are welded to the circular column. A total of 20 specimens are tested to clarify the structural behavior of the CFT column connections with the external stiffener rings. The test results are summarized for the yield and maximum strength and stiffness. The existing design equations for the allowable and yield load capacities are referred to verify the structural characteristics for the connections.

• Journal of Korean Association for Spatial Structures
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• v.12 no.4
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• pp.81-90
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• 2012

The concrete-filled tube (CFT) column has the excellent structural performance. But it is difficult to connect with column and beam because of closed section. Its Solution, 2 members of ㄷchennel in which Internal diaphragm is installed were welded beforehand and the method of making Rectangular Steel Tube was proposed. According to upside and downside junction shape, Internal diaphragm suggested as symmetric specimen and asymmetric specimen. The upper and lower diaphragm of the Symmetric specimen used the same horizontal and The upper diaphragm of the Asymmetric specimen used the horizontal plate and the lower diaphragm used the vertically plate. In this research, 4 T-shape column to beam steps connections were tested with cyclic loading experiment in order to evaluate the structural capability of the offered connection. Symmetric specimens be a failure in 0.03rad from beam flange. And Asymmetric specimens be a failure in 0.05rad from column interface. The comparison results of All specimens shown similar to energy absorption capacity in 0.02rad.

• Steel and Composite Structures
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• v.2 no.2
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• pp.147-160
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• 2002

This paper summarises results of the research performed at the Department of Steel Structures and Structural Mechanics from the "Politehnica" University of Timisoara, Romania, in order to evaluate the performance of beam-to-column extended end plate connections for steel and composite joints. It comprises laboratory tests on steel and composite joints, and numerical modelling of joints, based on tests. Tested joints are double-sided, with structural elements realised of welded steel sections. The columns are of cruciform cross-section, while the beams are of I section. Both monotonic and cyclic loading, symmetrically and antisymmetrically, has been applied. On the basis of tested joints, a refined computer model has been calibrated using a special connection element of the computer code DRAIN 2DX. In this way, a static/dynamic structural analysis of framed structures with real characteristics of the beam to column joints is possible.

• Steel and Composite Structures
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• v.20 no.2
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• pp.251-266
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• 2016

The paper combines two distinct parts. First the behavior of welded headed studs with small diameters of 10 and 13 mm acting as shear connectors (which are not embraced in current standards) is studied. Based on standard push tests the load-slip relationships and strengths are evaluated. While the current standard (Eurocode 4 and AISC) formulas used for such studs give reasonable but too conservative strengths, less conservative and full load-slip rigidities are evaluated and recommended for a subsequent investigation or design. In the second part of the paper the partially encased beams under bending are analyzed. Following former experiments showing rather indistinct role of studs used for shear connection in such beams their role is studied. Numerical model employing ANSYS software is presented and validated using former experimental data. Subsequent parametric studies investigate the longitudinal shear between steel and concrete parts of the beams with respect to friction at the steel and concrete interface and contribution of studs with small diameters required predominantly for assembly stages (concreting). Substantial influence of the friction and effect of concrete confinement was observed with rather less noticeable contribution of the studs. Distribution of the longitudinal shear and its sharing between friction and studs is presented with concluding remarks.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.9
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• pp.11-18
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• 2018

As the height of the modular buildings increases, their stability becomes more and more dependent on the core. All traditional construction methods in structural concrete and steel can be utilized for cores in modular buildings but a core system with dry connection is more desirable to complete a greater degree of factory finish and faster erection of modular buildings. In order to do that, the hybrid PC(precast concrete) panel, which has a pair of C-shaped steel beams combined at the top and bottom of a concrete wall, was developed, In this study the cyclic lateral loading test on the hybrid PC panel is carried out and the panel configurations are examined to enhance the structural performance in comparison with the RC wall. Experimental results show that the strength of hybrid PC panel is about 70% of thar ot RC wall and the anchorage of vertical reinforcing bar welded to C-shaped steel beam needs to be improved.

• Journal of Korean Society of Steel Construction
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• v.25 no.1
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• pp.35-45
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• 2013

The concrete-filled tube column has the excellent structural performance. But it is difficult to connect with column and beam because of closed section. It suggests that pipe should be produced by welding two sides together where two shapes are joined after a channel is pre-welded onto the three sides in order to form an internal diaphragm. The upper diaphragm of the connection used the horizontal plate and the lower diaphragm used the Vertical plate. This research performed 6 monotonic tension experiments describing the connection upside and downside in order to evaluate the structural capability of the offered connection. And the cyclic loading experiment was performed about 2 T-Type column to beam connections. As to the experimental result edge cutting geometry, there was no big effect. An increase in the number of holes of the plate ultimate strength was increased by 5% and The thickness of the plate increases, the maximum strength was increased by 4%. T-Type connections until it reaches the plastic moment showed a stable behavior.