• 한국안전학회지
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• 제25권1호
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• pp.57-61
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• 2010

Formwork is a temporary structure that supports its weight and that of fresh concrete as well as construction live loads. Scaffoling is a temporary frame used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes, although it can be made out of other materials. Bamboo is still used in some Asian countries like China. The purpose of a working scaffold is to provide a safe place of work with safe access suitable for the work being done. In construction site, steel pipes are usually used as scaffolds. In this study, scaffolding systems which is changed according to sleeper and joist space were measured by buckling test. Buckling load of respective scaffolding system was analyzed by structural analysis program(MIDAS). Buckling load of scaffold with/without wall connection and footboard was got by test and structural analysis. According to these results，we know that scaffolding system of case 3 is suitable. Buckling load of scaffold with wall connection is higher than without wall connection. So wall connection is important in scaffoling systems. Footboard in the scaffolding systems is not effective against promotion of buckling load. Finally, the present study results will be used to design scaffolding systems safely in the construction sites.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.530-533
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• 2006

This thesis investigates the behavior of precast wall systems with a new vertical connection which are proportioned by the displacement based design. The proposed precast wall systems are supposed to provide additional spaces and seismic strengthening in remodeling existing residential buildings. For a fast remodeling constructions using PC walls require an efficient, economic fabrication method. A C-type vertical connections for PC wall systems is proposed for transfer of bending moment between walls in the vertical direction while a shear key in the center of wall is prepared to transfer shear forces by bearing. The proposed vertical connection allows us easy fabrication because of different direction of slots at the edges of wall. The dimension of C-type connection components are determined by engineering models and a series of test.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2006년도 학술발표회 논문집
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• pp.217-224
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• 2006

This thesis investigates the behavior of precast wall systems with a new vertical connection which are proportioned by the displacement based design. The proposed precast wall systems are supposed to provide additional spaces and seismic strengthening in remodeling existing residential buildings. For a fast remodeling constructions using PC wails require an efficient, economic fabrication method. A C-type vertical connections for PC wall systems is proposed for transfer of bending moment between walls in the vertical direction while a shear key in the center of wall is prepared to transfer shear forces by bearing. The proposed vertical connection allows us easy fabrication because of different direction of slots at the edges of wall. The dimension of C-type connection components are determined by engineering models and a series of test.

• 한국지반신소재학회논문집
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• 제8권2호
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• pp.21-29
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• 2009

블록식 보강토옹벽의 설계 시 국부적 안정성 평가에 있어서 실험적 방법을 통한 전면블록과 보강재 사이의 연결강도에 대한 특성을 평가해야 한다. 그러나 NCMA 및 FHWA에서 제안하고 있는 연결강도 평가방법을 적용할 경우에는 다소 보수적인 평가결과 나타나게 된다. 따라서 본 연구에서는 전면블록과 지오그리드 보강재 사이의 연결강도 시험을 수행하였다. 또한 시험결과를 NCMA, FHWA 및 Soong & Koerner가 제안한 평가방법에 의해 블록식 보강토옹벽 설계사례에 적용하였다. 그 결과, Soong & Koerner에 의해 제안된 연결강도 시험으로부터 얻어진 극한연결강도를 허용연결강도로서 적용하여도 설계시 요구되는 안정성을 만족하는 것으로 나타났다.

• 콘크리트학회지
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• 제7권4호
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• pp.157-168
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• 1995

Slip-Form시스템을 사용하였을 때 공기단축 및 우수한 품질의 벽체타설이 가능하기 때문에, 그 적용성 및 구조적 거동을 평가하는 연구가 수행되었다. 그러나 슬래브를 벽체와 동시에 타설할 수 없기 때문에 벽체-슬래브 접합부의 주변에 취약점이 생기게 될 가능성이 있으므로, 본 연구는 Slip-Form시스템을 사용한 벽식 구조의 성능을 평가하고, 효과적인 접합부를 개발하는 것을 목적으로 하였다. 이를 위하여 7개의 벽체 실험체와 8개의 벽체-슬래브 접합부 실험체를 제작하여 실험을 실시하였다. 그리고 실험결과들을 설계식 및 이론적인 해석 결과와도 비교하였다. 벽체압축 실험으로부터 그 구조적 거동이 일체식 구조와 유사함을 알 수 있었으며, 벽체-슬래브 접합부 실험으로 부터는 철근연결용 철물이 있는 경우는 제외하고는 좋은 성능을 나타냄을 알 수 있었다. 그러나 외벽에 철근연결용 철물을 사용한 경우에는 벽체의 강도을 검토하여 설계에 반영하여야 함을 알 수 있었다.

• 한국지진공학회논문집
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• 제28권1호
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• pp.47-57
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• 2024

Recently, in newly constructed apartment buildings, the exterior wall structures have been characterized by thinness, having various openings, and a significantly low reinforcement ratio. In this study, a nonlinear finite element analysis was performed to investigate the crack damage characteristics of the exterior wall structure. The limited analysis models for a 10-story exterior wall were constructed based on the prototype apartment building, and nonlinear static analysis (push-over analysis) was performed. Based on the finite element (FE) analysis model, the parametric study was conducted to investigate the effects of various design parameters on the strength and crack width of the exterior walls. As the parameters, the vertical reinforcement ratio and horizontal reinforcement ratio of the wall, as well as the uniformly distributed longitudinal reinforcement ratio and shear reinforcement ratio of the connection beam, were addressed. The analysis results showed that the strength and deformation capacity of the prototype exterior walls were limited by the failure of the connection beam prior to the flexural yielding of the walls. Thus, the increase of wall reinforcement limitedly affected the failure modes, peak strengths, and crack damages. On the other hand, when the reinforcement ratio of the connection beams was increased, the peak strength was increased due to the increase in the load-carrying capacity of the connection beams. Further, the crack damage index decreased as the reinforcement ratio of the connection beam increased. In particular, it was more effective to increase the uniformly distributed longitudinal reinforcement ratio in the connection beams to decrease the crack damage of the coupling beams, regardless of the type of the prototype exterior walls.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.435-438
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• 2005

The use of new hybrid systems that combine the advantages of steel and reinforced concrete structures has gained popularity. One of these new mixed systems consists of steel beams and reinforced concrete shear wall, which represents a cost- and time-effective type of construction. A number of previous studies have focused on examining the seismic response of steel coupling beams in a hybrid wall system. However, the shear transfer of steel coupling beam-wall connections with panel shear failure has not been thoroughly investigated. The objective of this research was to investigate the seismic performance of steel coupling beamwall connections governed by panel shear failure. To evaluate the contribution of each mechanism, depending upon connection details, an experimental study was carried out The test variables included the reinforcement details that confer a ductile behaviour on the steel coupling beam-wall connection, i.e., the face bearing plates and the horizontal ties in the panel region of steel coupling beam-wall connections. It investigates the seismic behaviour of the steel coupling beams-wall connections in terms of the deformation characteristics. The results and discussion presented in this paper provide background for a companion paper that includes a design model for calculating panel shear strength of the steel coupling beam-wall connections.

• Journal of the Korean Wood Science and Technology
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• 제48권5호
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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.

• 대한건축학회논문집:구조계
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• 제35권10호
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• pp.155-162
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• 2019

Hybrid precast concrete panel is a wall element that is able to quickly construct the core wall structure for moderate-rise modular buildings. Hybrid precast concrete panel has unique characteristics which is a pair of C-shaped steel beams combined at the top and bottom of a concrete wall, In this study, an improved anchorage detail for vertical rebar is proposed to ensure the lateral force resistance performance of hybrid precast concrete panel emulating monolithic concrete wall. Also, the structural performance of horizontal connection is investigated experimentally with the bolt spacing parameter. And the behavior of hybrid precast concrete panel with the improved detail is compared with the monolithic concrete wall tested in a previous study. Finally, the required thickness of C-shaped steel beam to eliminate or minimize the deformation in horizontal connection is calculated by prying action equation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.138-141
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• 2006

Shear wall-frame system is one of the most, if not the most, popular system for resisting lateral loads. The core is the primary lateral load-resisting systems, the perimeter frame is designed for gravity loads, and the connection between perimeter frame and core is generally a shear connection. Specially, single plate shear connection have gained considerable popularity in recent years due to their ease of fabrication and erection. Single plate shear connection should be designed to satisfy the dual criteria of shear strength and rotational ductility. An experimental program was undertaken to evaluate seismic behavior of single plate shear connection. The main test variable is the reinforcing detail of connection. Through the experimental program, the cyclic behavior of typical and reinforcing single plate shear connection was established.