• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.324-327
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• 2008

We simulated the performance improvement of a wind turbine installed on the pitched roof-building(apartment in urban area, 50m height). A nozzle shape wind guide is added on the roof of a model apartment. The nozzle-diifuser structure effects for the free stream wind (average 4m/s, 50m height in Incheon) is studied by a basic CFD analysis. This paper examines the effects of roof structure on the wind velocity and the wind distortion effects by a front building. The possible wind power generation capacity on building roof in urban is calculated.

• Structural Engineering and Mechanics
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• 제29권1호
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• pp.37-53
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• 2008

Plane steel portal frames, with pitched roof, exposed to fire, are examined. First, a determinate frame is analysed by hand. For flexible columns and shallow roof, snap-through occurs before plastic hinges mechanism is formed. An indeterminate frame with shorter columns and taller roof is also analysed by hand. Then, the same frame is simulated by a truss and a nonlinear static analysis is performed by use of a short computer program. The results of computer analysis by use of truss model are compared with those of analysis by hand and a satisfactory approximation between them is observed.

• 한국농공학회지
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• 제36권3호
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• pp.84-89
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• 1994

Section forces of greenhouse structures were studied to suggest basic information for the structural design of greenhouses with respect to roof types and support conditions. Structural analyses were performed for pitched and arched roof, and fixed and hinged support under snow loads and wind loads. Followings are the results obtained and are expected to be useful in determining the span length and roof type in greenhouse design. 1. Special considerations might he required for roof design at the heavy snow region, and for the support design at the strong wind region, respectively. 2. Single-span structure was found to be stronger than multi-span structure under the snow load, but the former was found to be weaker than the latter under the wind load. 3. Arched roof structure was expected to be safer than pitched roof structure if the dimensions and loads were equal. 4. Greenhouse orientation and roof slope should be considered in optimum structural design of grrenhouses, because these two factors are closely related with the influence of wind load and snow load.

• Wind and Structures
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• 제22권3호
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• pp.307-328
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• 2016

This paper describes an investigation of the net wind loads on solar panels and wind loads on the underlying roof surface for panels mounted parallel to pitched roofs of domestic buildings. Typical solar panel array configurations were studied in a wind tunnel and the aerodynamic shape factors on the panels were put in a form appropriate for the Australian/New Zealand Wind Actions Standard AS/NZS 1170.2:2011. The results can also be used to obtain more refined design data on individual panels within an array. They also suggest values for the aerodynamic shape factors on the roof surface under the panels, based on a gust wind speed at roof height, of ${\pm}0.5$ for wind blowing parallel to the ridge, and ${\pm}0.6$ for wind blowing perpendicular to the ridge. The net loads on solar arrays in the middle portion of the roof are larger than those on the same portion of the roof without any solar panels, thus resulting in increased loads on the underlying roof structure.

• 신재생에너지
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• 제5권4호
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• pp.21-27
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• 2009

Potential yield of micro wind turbine on the roof of urban high rise buildings is estimated. Urban wind profile is modeled as logarithmic profile above the mean building height with roughness length 0.8, displacement 7.5 m. Mean wind velocity from the meteorological agency data at the hight of 50m is used. Wind velocity changes are simulated on the rectangular roof of 26, 45, 53 degree pitch and the circular roof by computational fluid dynamics and RNG k-$\varepsilon$ turbulence models. Wind velocity increased approximately by a factor of the order of 270 % on the 26 degree pitched roof. In the 100 m and 200 m high buildings, wind enhancement is greater at the front side than at the center of the building. In the building arrangement model wind velocity changes abruptly and it becomes wind gusts. When commercial wind turbines are installed on the building roof, average power and annual power generation enhanced by 3~4 times than normal wind velocity at 50m and 6 kw wind turbine can generate 1053 kwh per month on the 26 degree pitched roof at 50m height and sufficiently supply electrical power with 15 household for common electrical use and food waste disposer. However, power output will vary significantly by the wind conditions in the order of $\pm$ 20 %.

• Smart Structures and Systems
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• 제19권6호
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• pp.643-652
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• 2017

Pitched roof frames are widely used in construction of the industrial buildings, gyms, schools and colleges, fire stations, storages, hangars and many other low rise structures. The weight and shape of the gable frames with tapered members, as a familiar group of the pitched roof frames, are highly dependent on the properties of the member cross-sectional. In this work Enhanced Colliding Bodies Optimization (ECBO) is utilized for optimal design of three gable frames with tapered members. In order to optimize the frames, the design is performed using the AISC specifications for stress, displacement and stability constraints. The design constraints and weight of the gable frames are computed from the cross-section of members. These optimum weights are obtained using aforementioned optimization algorithms considering the cross-sections of the members and design constraints as optimization variables and constraints, respectively. A comparative study of the PSO and CBO with ECBO is also performed to illustrate the importance of the enhancement of the utilized optimization algorithm.

• 한국지역지리학회지
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• 제21권4호
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• pp.660-672
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• 2015

촌락 가옥은 촌락 경관을 구성하는 중요한 요소이다. 기존의 촌락 가옥에 대한 지리학 연구는 주로 전통적인 민가에 초점을 두었으나, 본 연구는 오늘날의 촌락 가옥에 초점을 둔다. 본 연구는 경남 도서지역 가옥의 지붕 형태와 지붕 재료를 중심으로 제시하는 촌락 가옥의 유형에 관한 연구이다. 연구지역의 가옥에 대한 조사 결과를 바탕으로 해서 지붕 형태와 지붕 재료를 분류하는 기준을 제시하고, 이에 따른 촌락 가옥의 유형화를 시도한다. 지붕 형태를 중심으로 분류하는 가옥 유형에서는 팔작지붕 우진각 맞배지붕과 같은 전통적인 지붕 형태를 가진 가옥이 많고, 전통적인 지붕 형태 이외의 가옥 유형에서는 단순평지붕 가옥이 많다. 두 개 이상의 지붕 형태를 가진 결합양식지붕 가옥 유형의 경우, 경사-평지붕 가옥이 경사-경사지붕 가옥보다 10여 배나 많다. 지붕 재료 중에서는 시멘트, 컬러강판, 인조슬레이트가 가장 많이 사용된다. 특정 지붕 재료가 특정 지붕 형태에서 두드러지게 사용되는 경우가 있는데, 이를 통해 연구지역의 주요한 가옥 유형을 '지붕 재료와 지붕 형태'를 중심으로 다섯 가지로 유형화할 수 있다.

• 한국태양에너지학회 논문집
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• 제21권3호
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• pp.9-18
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• 2001

This paper reports on an theoretical study of heat transfer from evaporative cooling system by the flow of recirculated water over the roof. In this system tile water is distributed at the top of the pitched roof, collected at the bottom by a gutter and recirculated by a pump. To analysis the system, the energy balance equations are developed and solved using a finite difference method. The calculation results show a good agreement with the measured ones obtained from our experiment. Based on the results, it was seen that the roof-evaporative cooling system reduced the heat flux significantly compared with the conventional roof structure even in the hot-humid summer climate of Korea.

• 대한건축학회논문집:계획계
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• 제35권7호
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• pp.81-88
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• 2019

The purpose of this study is to investigate the relations between brick and stone brick pagodas in all classes of pagoda with their construction and shape. Research objects of this study are brick and stone brick pagodas of National Treasure and Treasure and masonry pagodas that are similar to brick and stone brick pagoda. This study includes checking preceding researches, drawing questions from these preceding researches, and finding answers from these questions. The results of this study are as follows. First, pagoda of Bunhwangsa Temple, the first pagoda in the Silla Dynasty, was built as a masonry pagoda, not a stone brick pagoda. Second, roofs of stone brick pagoda barrows from brick pagoda's techniques for performance of material and ease construction. Third, brick or stone brick pagodas' base have Type II that has low and extensive foundation with soil and stones usually. Forth, Korean pagodas are categorized by their materials, construction methods, and shapes. Wooden pagodas, stone pagodas, and brick pagodas are categorized by materials, post-and lintel pagodas and masonry stone pagodas are categorized by construction methods, and pitched roof pagodas and terraced roof pagodas are categorized by shapes. Fifth, masonry pagodas of Buddhism that have shape of multi-story building were developed from Doltap, traditional stone stack, and they advanced with brick pagodas and stone pagodas to terraced roof stone pagodas and post-and lintel base brick pagodas.

• Steel and Composite Structures
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• 제4권2호
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• pp.77-94
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• 2004

Steel beam-to-column joints are often subjected to a combination of bending and axial forces. The level of axial forces in the joint may be significant, typical of pitched-roof portal frames, sway frames or frames with incomplete floors. Current specifications for steel joints do not take into account the presence of axial forces (tension and/or compression) in the joints. A single empirical limitation of 10% of the beam's plastic axial capacity is the only enforced provision in Annex J of Eurocode 3. The objective of the present paper is to describe some experimental and numerical work carried out at the University of Coimbra to try to extend the philosophy of the component method to deal with the combined action bending moment and axial force.