• 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.

• 한국구조물진단유지관리공학회 논문집
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• 제3권3호
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• pp.253-260
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• 1999

Main objective of this study is to examine the hysteretic behaviors and to evaluate the capacity of precast concrete (PC) large panel structures simulated from the prototype of 15-story building, Two 1/2 scaled precast concrete wall specimens and one monolithic reinforced concrete specimen were designed and tested under the cyclic loading conditions. The main parameter of test specimens in PC large panel structure is the type of details for vertical continuity of vertical steel in horizontal joint. Also the behaviors of PC large panel structures are compared with that of monolithic reinforcement concrete wall structure. From the results, the stiffness and energy dissipation ratio of the precast concrete specimens are shown little bit lower than those of monolithic reinforced concrete specimen. In the PC large panel structures, the specimen connected vertically by welding (strong connection) showed higher strength than that of the specimen connected vertically by joint box. However the failure pattern of the former showed more brittle than that of the latter due to the diagonal compressive failure of wall panels.

• 복합신소재구조학회 논문집
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• 제6권2호
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• pp.52-62
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• 2015

This study aims at developing a new seismic resistant method by using precast concrete wall panels for existing low-rise, reinforced concrete beam-column buildings such as school buildings. Three quasi-static hysteresis loading tests were performed on one unreinforced beam-column specimen and two reinforced specimens with U-type precast wall panels. Top shear connection of the PC panel was required to show the composite strength of RC column and PC wall panel. However, the strength of the connection did not influence directly on the ultimate loading capacities of the specimens in the positive loading because the loaded RC column push the side of PC wall panel and it moved horizontally before the shear connector receive the concentrated shear force in the positive loading process. Under the positive loading sequence(push loading), the reinforced concrete column and PC panel showed flexural strength which is larger than 97% of the composite section because of the rigid binding at the top of precast panel. Similar load-deformation relationship and ultimated horizontal load capacities were shown in the test of PR1-LA and PR1-LP specimens because they have same section dimension and detail at the flexural critical section. An average of 4.7 times increase in the positive maximum loading(average 967kN) and 2.7 times increase in the negative maximum loading(average 592.5kN) had resulted from the test of seismic resistant specimens with anchored and welded steel plate connections than that of unreinforced beam-column specimen. The maximum drift ratios were also shown between 1.0% and 1.4%.

• 복합신소재구조학회 논문집
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• 제6권2호
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• pp.105-117
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• 2015

The purpose of this study is to develop a new seismic resistant method by using precast concrete wall panels for existing low-rise, reinforced concrete beam-column buildings such as school buildings. Three quasi-static hysteresis loading tests were experimentally performed on one unreinforced beam-column specimen and two reinforced specimens with L-type precast wall panels. The results were analyzed to find that the specimen with anchored connection experienced shear failure, while the other specimen with steel plate connection principally manifested flexural failure. The ultimate strength of the specimens was determined to be the weaker of the shear strength of top connection and flexural strength at the critical section of precast panel. In this setup of L-type panel specimens, if a push loading is applied to the reinforced concrete column on one side and push the precast concrete panel, a pull loading from upper shear connection is to be applied to the other side of the top shear connection of precast panel. Since the composite flexural behavior of the two members govern the total behavior during the push loading process, the ultimate horizontal resistance of this specimen was not directly influenced by shear strength at the top connection of precast panel. However, the RC column and PC wall panel member mainly exhibited non-composite behavior during the pull loading process. The ultimate horizontal resistance was directly influenced by the shear strength of top connection because the pull loading from the beam applied directly to the upper shear connection. The analytical result for the internal shear resistance at the connection pursuant to the anchor shear design of ACI 318M-11 Appendix-D except for the equation to predict the concrete breakout failure strength at the concrete side, principally agreed with the experimental result based on the elastic analysis of Midas-Zen by using the largest loading from experiment.

• 한국지반공학회논문집
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• 제37권3호
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• pp.43-50
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• 2021

우리나라는 산지가 많은 지형적인 특성으로 도로와 도시 개발에 따라 산지를 굴착하고 옹벽을 설치하는 공사가 매년 증가하고 있다. 특히 Panel식 옹벽은 안정성이 높기 때문에 사용빈도가 높으며, 일반적으로 Bottom-up방식을 사용하고 있다. 하지만 옹벽을 설치하기 위해 1:0.3정도의 기울기로 굴착 후 옹벽을 시공하는 방식인데 이러한 방식은 경사굴착으로 인해 추가 토공처리가 필요하며, 되메움과 다짐불량에 의한 안정성 저하 등의 문제점을 지니고 있다. Top-down방식의 경우 이러한 문제점을 보완할 수 있다. 하지만 Panel을 사면에 부착시키기 위해 사용되는 모르타르로 인해 옹벽과 사면 사이에 불투수층이 생긴다. 따라서 본 연구에서는 가상의 사면에 불투수층을 고려하여 배수시스템들의 역할이 우기시 사면의 안정성에 미치는 영향에 대하여 비교 분석하였다.

• 한국지반공학회논문집
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• 제36권12호
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• pp.99-106
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• 2020

우리나라는 산지가 많은 지형적인 특성으로 교통의 편리를 위해 산지를 절취하여 변형시키는 공사가 매년 증가하고 있다. 특히 산지를 절치하여 변형시킬 경우 자연재해로 인한 사면 붕괴, 환경문제 등의 문제가 발생한다. 이러한 문제를 해결하고자 판넬식 옹벽, 보강토 옹벽 등의 다양한 보강공법이 있다. 하지만 Bottom-up방식의 경우 경사굴착으로 인한 추가 토공처리가 필요하며 되메움과 다짐불량에 의한 안정성 저하 등의 문제점을 지니고 있다. 따라서 본 연구에서는 기존 Bottom-up방식의 문제점을 해결하기 위해 Top-down방식에 대해 현장 적용시험 및 수치해석을 통해 안정성 분석을 수행하였으며, 대표단면을 선정하여 Bottom-up방식과 Top-down방식에 대해 안정성 비교분석하였다.

• Advances in concrete construction
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• 제9권5호
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• pp.437-448
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• 2020

In high rise buildings that utilize precast large panel system for construction, the shear wall provides strength and stiffness during earthquakes. The performance of a wall panel system depends mainly on the type of connection used to transfer the forces from one wall element to another wall element. This paper presents an experimental investigation on different types of construction detailing of the precast wall to wall vertical connections under reverse cyclic loading. One of the commonly used connections in India to connect wall to wall panel is the loop bar connection. Hence for this study, three types of wet connections and one type of dry connection namely: Staggered loop bar connection, Equally spaced loop bar connection, U-Hook connection, and Channel connection respectively were used to connect the precast walls. One third scale model of the wall was used for this study. The main objective of the experimental work is to evaluate the performance of the wall to wall connections in terms of hysteretic behaviour, ultimate load carrying capacity, energy dissipation capacity, stiffness degradation, ductility, viscous damping ratio, and crack pattern. All the connections exhibited similar load carrying capacity. The U-Hook connection exhibited higher ductility and energy dissipation when compared to the other three connections.

• 대한건축학회논문집:구조계
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• 제34권9호
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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.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.87-96
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• 2010

PAP method is a combined measures which consist a anchored retaining wall method with permanent ground anchors and vertical precast concrete panels, step by step on the slope surface. And soil is back filled between slope and vertical precast panels. Therefore, this method is more effective than any other ground anchor reinforcing methods of slope stability, for example cross type concrete block ground anchor or buttress concrete block ground anchor method. Because of increasing effective anchor force and green tree planting.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.459-460
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• 2009

PC(Precast Concrete)구조시스템은 건식화 조립식 공법으로 구조물 건설에 있어 공기, 노동력 절감 등의 여러 장점을 가지고 있다. 하지만 구조벽체의 경우 PC화할 경우 접합부의 내진성능이 부족하여 구조벽체를 PC화하여 적용하는 경우는 드물다고 할 수 있다. 본 연구에서는 이러한 점을 감안하여 접합부 성능을 개선하여 횡력저항요소로 사용가능한 PC구조벽체를 고안하였다. 제안된 PC구조벽체는 지진발생 시 충분한 강도와 변형능력을 확보할 수 있도록 하였다. 제안된 PC구조벽체의 실험결과, 제안된 PC구조벽체는 충분한 내진성능을 확보할 수 있는 것으로 나타났다.