• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.885-890
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• 2000

12 RC deep beams with a/d = 1.17 are reported. This paper is to study the effect of vertical and horizontal web reinforcement and web reinforcement arrangement on inclined cracking shear, ultimate shear strength, midspan deflection, and inclined crack width. Test results indicated that web reinforcement produces and arrangement seems to moderately affect inclined cracking shear, ultimate shear strength and crack width. However, addition of horizontal web reinforcement(pv = 0.0085) little or no influence on inclined cracking shear, ultimate shear strength and crack width. The member which vertical and horizontal web reinforcement concentrate on the center web considerably increases in load-carrying capacity.

• 한국구조물진단유지관리공학회 논문집
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• 제25권5호
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• pp.76-85
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• 2021

이 연구에서는 유공보강근의 형상에 따른 RC 유공보의 구조성능을 평가하기 위하여 전단실험을 수행하였다. 실험체는 총 4체이며, 주요변수는 유공의 유무, 유공 보강 유무, 유공 보강근의 형상이다. 이 연구에서는 사각형과 팔각형이 혼합된 나선형의 유공보강근을 개발하였으며, 이를 기존 Band형과 비교하였다. 실험결과, 제안 유공 보강근으로 유공을 보강한 실험체는 타 실험체에 비하여 최대 전단력과 최대 전단력 이후 에너지소산면적이 증가하는 것으로 나타났다. 따라서 제안 유공 보강근은 유공 주위의 균열제어와 함께 전단성능의 향상에 효과적임을 확인하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제22권4호
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• pp.19-26
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• 2018

이 연구는 유공보강근의 형상에 따른 철근콘크리트 유공 보의 전단저항성능을 평가하기 위하여 4체의 실험체를 제작하여 전단실험을 수행하였다. 실험의 주요변수는 유공의 유무, 유공보강 유무, 유공 보강근의 형상으로 하였으며, 제안 유공 보강근은 시공성을 고려하여 사각형과 마름모형이 혼합된 나선형 형태이다. 실험결과, 이 연구에서 제안된 유공보강근은 유공 주변의 균열을 효과적으로 제어하여 실험체의 전단력 향상에 효과적임을 확인하였다. 또한 현행설계기준은 유공 보강근을 배근한 실험체의 실험결과를 과소평가하는 것으로 나타났다.

• 한국농촌건축학회논문집
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• 제24권2호
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• pp.13-20
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• 2022

In this study, a general low-rise building was selected to compare the new shear wall reinforcement method, which is a general method among the existing reinforcement methods, and the reinforcement method using sinusoidal corrugated web reinforcement. And it was confirmed that the following effects can be expected. Sinusoidal corrugated web members can be carried out in a short period of time as it does not require the removal of the masonry filling wall, the reinforcement of reinforcing bars, and the curing period of the concrete. It is effective in preventing damage that may occur when masonry filling wall is overturned in the out-of-plane direction, and the burden of the foundation is also reduced, and thus the construction period and cost required for reinforcement can greatly be reduced. By adjusting the number of sinusoidal corrugated web member, details of joints, and reinforcement positions, the flow of load can be induced to have an advantageous effect on the building. It can be considered as the most suitable reinforcement plan in terms of life safety. Unlike the shear wall that fills between the columns, the sinusoidal corrugated web members, which has a width of 1.5m, can install openings between two columns depending on the purpose of use, and can be expected to have a great effect in terms of usability due to its free installation location. As mentioned above, the seismic reinforcement using a sinusoidal corrugated web members, can expect great effect compared to conventional reinforcement methods in terms of usability, economic feasibility, and stability.

• 한국지능시스템학회논문지
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• 제15권4호
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• pp.395-399
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• 2005

본 논문에서는 특정 주제에 관한 웹 문서들을 더욱 빠르고 정확하게 탐색하기 위하여 강화학습을 이용한 HIGH-Q 학습 알고리즘을 제안한다. 강화학습의 목적은 환경으로부터 주어지는 보상(reward)을 최대화하는 것이며 강화학습 에이전트는 외부에 존재하는 환경과 시행착오를 통하여 상호작용하면서 학습한다. 제안한 알고리즘이 주어진 환경에서 빠르고 효율적임을 보이기 위하여 넓이 우선 탐색과 비교하는 실험을 수행하고 이를 평가하였다. 실험한 결과로부터 우리는 미래의 할인된 보상을 이용하는 강화학습 방법이 정답을 찾기 위한 탐색 페이지의 수를 줄여줌으로써 더욱 정확하고 빠른 검색을 수행할 수 있음을 알 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 봄 학술발표회 논문집
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• pp.85-90
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• 1994

Three high strength reinforced concrete structural walls were tested under the combined action of a constant axial and a horizontal cycle load. The aim of the tests has been to investigate the effects of the web horizontal reinforcement on hysteretic behavior of wall. The results have helped to identify the causes of wall failure and have demonstrated the web horizontal reinforcement does not appear have a significant effect on shear capacity, stiffness and energy dissipation but have a significant effect on the failure mode of the walls.

• Asia pacific journal of information systems
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• 제16권4호
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• pp.179-202
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• 2006

The objective of this study is to identify the impacts of communication reinforcement on performance of learning in Web-PBL. Communication reinforcement is defined as the combination of information sharing and co-construction. As factors facilitating communication reinforcement, we propose learner's characteristics, task characteristics, and group characteristics. Learner's characteristics are collaboration-orientation, openness, holistic approach, and online community-orientation which reflects e-learning environment. Collaboration-oriented tasks as group projects were developed and given to groups with 5-6 members. The group characteristics are categorized into 'horizontal' and 'vertical', according to the patterns of communication between a group leader and members. To verify empirically the proposed research model, an experimental design was performed to learners who took on-line and off-line courses with group projects. We found important results as follows; First, field dependence has positive impacts on information sharing, and online community-orientation has positive impacts on co-construction. These results correspond with prior studies on relationship between field dependence and collaborative learning. Second, collaboration-oriented task directly impacts on information sharing, and indirectly affects co-construction, This result implicates that information sharing is pre-requisite of co-construction. Third, 'horizontal' was identified as a factor giving positive effects on information sharing and co-construction. This result implies that horizontal communication is very important to facilitate communication reinforcement.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.897-902
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• 2001

The purpose of this experimental study is to investigate the shear behavior of high-strength concrete deep beam and to grasp the conservatism of ACI Building Code. Experimental results on 12 deep beams under two equal symmetrically placed point loads are reported. Main variables are vertical and horizontal web reinforcement and shear span-to-overall depth ratio. Test results indicated that web reinforcement dose not affect on formation of inclined cracks but shear span-to-overall depth ratio affect on inclined shear cracks and ultimate shear strength. Addition of vertical web reinforcement improves ultimate shear strength of H.S.C. deep beams that shear span-to-overall depth ratio is 1.0. Considerable increase in ultimate shear strength of H.S.C. deep beams with increasing horizontal web reinforcement that shear span-to-overall depth ratio is 0.5. Especially with increasing concrete strength($f_{ck}$) the ACI code is conservative in estamating the ultimate shear strength of deep beams.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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• pp.184-189
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• 1993

This is an experimental investigation the shear behavior of reinforced concrete with stirrup of which stress ranges 0.0㎏/㎠ to 7.0㎏/㎠. Five rectangular beams which concrete strengths are 287㎏/㎠ and 380㎏/㎠, a/d=3, and main steel ratio equal to 1.96% was tested. Those were designed to fail in shear. The shear cracking load and failure load were measured and compared with ACI's equation and Zutty's proposed equation. The results are following : ACI equation and Zutty's equation are consertive. As the concrete compressive strength increased, reserved shear strength of beams with minimum web reinforcement decreases. According to increase of web reinforcement , the rate of increases of shear strength is decreased. The failure modes of specimen with minimum web reinforcement are shear compression failure which is reached after diagonal shear cracking.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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• pp.331-338
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• 1995

Results of an experimental of the shear and flexures strength of doubly reinforced concrete beams were summarized. A total of 24 beams was tested; 4 without web reinforcement and 20 with web reinforcement in the form of vertical stirrups. Main variables were compressive strength of concrete which was 26.88MPa and 63.4MPa, spacing of stirrups which was no-stirrups, 200, 150, 120, 100 and 90mm. Tests results were compared with stength predicted using the equations of ACI 318-89. The shear reinforcement ratio of the beams, which failed simultaneously under both flexures and shear, were 0.66pvmax for low strength concrete beams and 0.56pvmax for high strength concrete beams, respectively. Thus, ACI equations for shear reinforcement were very conservative.