• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.535-540
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• 2000

When the stud connection is considered as pin joint in the practical design, it is required to have high deformability. The rotational capacity as well as moment of the connection are evaluated through experimental works. Considered in the test are the reinforcement ratios of concrete member, the magnitude of axial force and connection details. It is shown that the stud connection has some quantity of moment capacity buy on the other hand it has low deformability. The strength and deformability of the connection depend on the axial force and reinforcements around the studs. The strength and ductility of the connection ate increased by using closed C-type.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.213-216
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• 2005

A numerical analysis was performed for interior connections of continuous flat plate to analyze the effect of design parameters such as column section shape, gravity load and slab span on the behavioral characteristics of the connections. Through the parametric study, the variations of shear stress distribution around the connection were investigated. According to the result of numerical analysis, as the length of the cross section of column in the direction of lateral load increases and gravity load increases, the effective area and the maximum shear strength providing the torsional resistance decrease considerably. And as the slab span loaded with relatively large gravity load increases, the negative moment around the connection increases and therefore the strength of connection against unbalanced moment decreases.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.102-105
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• 2006

Nowadays, increase of demands on efficient utilization of resources while construction process stimulates structural engineers to select remodeling to improve old buildings. To analyze the effects of openings that may be installed in the course of remodeling old buildings, an experimental research was carried out using four approximately half scale of specimens subjected to constant axial forces, and cyclic loading to simulate seismic conditions. Consequently, the existence of opening was verified to induce different observed damages, which caused by reduction of compression strut support formed on the surface of wall. Especially, the maximum force was revealed to decrease approximately 35% as openings were existed. As this tendency was appeared with stiffness and energy dissipation capacity.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.234-237
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• 2006

A series of three shear wall specimens was tested under constant axial stress and reversed cyclic lateral loading in order to evaluate the seismic retrofit that had been proposed for the shear wall with the opening induced by remodeling. One of these specimens was tested in the as-built condition and the other two were retrofitted prior to testing. The retrofit involved the use of carbon fiber sheets and steel plates (thickness of 3mm) over the entire face of the wall. The test results show that the ultimate failure modes of the specimens were found to be shear fracture of the wall around the opening and two difference types of retrofitting strategy make the different effects of a rise in the strength of each specimen.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.727-732
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• 2000

Four 1/2-scale wall specimens with flange are tested. The purpose of this study is to investigate experimentally structural behavior of flanged walls in wall slab system apartment buildings considering effective width of flange wall. Main variables are the length of web wall and concrete strength. Cyclic lateral loads are applied at the top of the walls. A constant axial load of approximately $0.1f_{ck}\cdotA_g$ is maintained during the testing. Test result shows that the capacity of the wall was governed by aspect ratios rather than concrete strengths and that initial stiffness and strength of specimens is increased with increasing the stiffness of web wall.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.757-762
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• 2000

The purpose of this study is to investigate the performance of slab-beam-column subassemblage in the Ordinary Moment Frame(OMF). For this purpose, 3-story building was designed according to UBC and ACI building code(ACI 318-99) and the subassemblages of in the first story were constructed. The subassemblages were classified into interior and exterior. Each interior and exterior subassemblage is modeled by the 2/3 scale experimental specimens. All the specimens have the transverse beam and the columns on the slab have the lap splice as the typical exterior and interior slab-beam-column subassemblage. The interior subassemblage was tested under the constant axial force, while the exterior subassemblage was tested under the fluctuating axial force. Based on the results of the experiments, the performance of each subassemblage is evaluated and the failure mode is investigated.

• Magazine of the Korea Concrete Institute
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• v.5 no.1
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• pp.175-181
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• 1993

콘크리트 구조체공사의 가장 큰 영향을 미치는 것은 거푸집공사이며, 구조체공사의 합리적 관리는 거푸집공사의 작업생산성에 관한 기초자료를 확보함으로써 가능하다. 본 연구에서는 거푸집공사의 과학적 관리기반을 구축하기 위하여, 구조체 기준층을 대상으로 작업측정을 하여 유로폼공법, 재래식 거푸집공법 등 주요공법의 생산성을 도출하였다. 또한, 거푸집공사의 주요 작업인 조립, 해체, 운반등 단위 공정의 소요작업 품을 산출함으로써, 작업개선을 위한 실용적인 자료를 제시하였다. 마지막으로 거푸집 면적이 생산성과 상관관계가 매우 높다는데 착안하여 소요작업품을 예측할 수 있는 상관관계식을 유도함으로써, 공정관리 및 기능공의 수급예측이 가능토록 하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.207-210
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• 2003

As reviewing of current trend on PC connection details, owing to effective stress transfer in the connection, it grow to increase that use of mechanical splices, reinforcements or welded splices, and prestressing. However such devices as reinforcement, mechanical splices entail not only more cost resulted from materials but also extra construction process so as to cause PC used method to lower competition against conventional method. Therefore more enhanced connection details which help working process simplified and construction cost reduced. In this research, as replace 9.3mm 7strand for reinforcement, it is attempt to devise connection detail which makes workability improve and confirm effective stress transfer in the region of connection. The experimental research is proceeded by partial tension test of specimen. The splice lengths of 7strand is decided to be variations. The flexural capability is verified to depend on spice length. An an appropriate splice length could be also determined as a precedent research on improving PC connection detail.

• 건강소식
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• v.12 no.5 s.114
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• pp.14-22
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• 1988

오늘날의 사회에서 일정한 시기가 되면 직업을 갖는 것은 당연한 일이다. 그런데 사회가 복잡다양해 지면서 직업을 갖는 것도, 자신의 직업을 충실히 엮어 나가는 것도 쉽지 않은 것 같다. 모든 것이 갈수록 치열한 경쟁 속으로 치닫고 있는 상황에서 직장인들은 새벽부터 밤늦게까지 이리뛰고 저리뛰고, 그런 사회관계 속에서 온갖 스트레스를 받게 된다. 그뿐이랴! 업무상 어쩔 수 없이 마시게 되고 스트레스 푼다고 또 한잔하게 되는 술, 돌아가지 않는 머리 회전을 위해 빨아대는 담배들. 그러나 직업이란 대체 무엇인가! 편안히 먹고살기 위한 과정이요 수단(?)이 아닐까? 그렇다면 스스로 돌보지 않은 건강에 누가 관심을 가져 주겠는가. 숨돌릴 틈도 없이 쌓여오는 일 속일지라도 단 1분만이라도 고개를 들 수 있는 여유를 갖고 나의 건강을 위해 무엇을 할 것인지 생각해 봐야겠다.

• Journal of the Korea Concrete Institute
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• v.14 no.2
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• pp.199-206
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• 2002

The objective of this study is to investigate the seismic behavior and evaluate structural performance of columns in Ordinary Moment Resting Concrete Frames (OMRCF). For this purpose 3 story OMRCF building was designed and detailed in compliance to ACI 318 (1999). Only gravity load is considered for the design. It is important to note that details strongly relate to the structural performance. The 1st story columns in the 3 story building are considered in this study since 다lese columns shall resist the largest axial and lateral forces during an earthquate. Four test specimens were made for representing the upper part and lower part of exterior and interior columns. All specimens are two-third scale. Based on the test results this study estimates deformation, ductility, strength, and energy absorption capacities as well as plastic hinge length.