• 제목/요약/키워드: wind property

검색결과 159건 처리시간 0.024초

엔지니어링 PE방수.방근시트가 결합된 박스 유닛형 옥상 녹화 시스템 적용을 위한 성능평가 (Performance Evaluation for the Application of Roof Green Box Unit System Combined with Engineering P.E.Waterproof and Root Penetration Sheet)

  • 오창원;홍종철;박기봉
    • 한국건축시공학회지
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    • 제16권2호
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    • pp.125-131
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    • 2016
  • 도심지 건물의 증가는 친환경 공간에 대한 요구를 발생시키고, 이에 따라 옥상 및 인공지반 녹화의 보급이 급속히 증가되고 있다. 본 연구는 녹화시스템의 보급 확대를 위해 공법의 단순화, 일체화, 프리훼브화 개념을 적용, 연속 토양층 형성 박스 유닛형 녹화시스템을 개발하고, 이 시스템의 주요 성능으로 부착성, 내풍성, 단열성을 평가하여 적용 가능성을 검토하였다. 부착성 및 내풍성 시험결과, 설계 풍압 및 풍속과 비교하면 100m 높이의 건물에 설치해도 안전한 것을 확인하였고, 단열성 평가를 위해 120일간 측정한 내부 온도의 변화를 분석한 결과, 개발 시스템이 연속된 토양층을 형성하여 기존 유닛박스 시스템보다 주간은 17%, 야간은 45% 우수한 단열성능을 보여 주었다.

The slenderness effect on wind response of industrial reinforced concrete chimneys

  • Karaca, Zeki;Turkeli, Erdem
    • Wind and Structures
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    • 제18권3호
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    • pp.281-294
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    • 2014
  • There are several parameters affecting the response of industrial reinforced concrete (RC) chimneys, i.e., the severity of wind and earthquake loads acting to the structure, structural properties such as height and cross section of the chimney, the slenderness property of the structure etc. One of the most important parameter that should be considered while understanding the wind response of industrial RC chimneys is slenderness property. Although there is no certain definition for slenderness effect on these structures, some standards like ASCE-7 define slenderness from different aspects of the structural properties. In the first part of this study, general information about the definition of slenderness in the well-known standards and ten selected industrial RC chimneys are given. In the second part of the study, brief information about wind load standards that are used for calculating wind loads namely ACI 307/98, CICIND 2001, DIN 1056, TS 498 and Eurocode 1 is given. In the third part of the study, calculated wind loads for selected chimneys are represented. In the fourth part of this study, the internal forces obtained from load combinations that are applied to chimneys and some graphs presenting the effect of slenderness on chimneys are given. In the last part of the study, a conclusion and discussion part is taking place.

Sensitivity and vibration reduction of buffeting induced resonance of hangers

  • Zhang, Zhitian;Zhang, Weifeng
    • Wind and Structures
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    • 제25권1호
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    • pp.39-61
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    • 2017
  • Buffeting induced resonance (BIR) of hangers on long-suspension bridges is briefly reviewed, including mechanism and experimental verification. Taken the Xihoumen suspension bridge as a numerical example, sensitivities of the BIR of hangers to wind properties are investigated, including types of wind spectrum, turbulence intensity, and spacial coherence of wind fluctuations. Numerical simulations indicate that the BIR of hangers occur to both cases of different wind spectra, showing that it is insensitive to types of wind spectrum. On the other hand, it is found that the turbulence intensity affects buffeting of main cables almost in a linear manner, and so it does to the BIR of the hangers; however, the resonance factors, namely the ratio of the response of the hanger to that of the main cable, are little affected by the turbulence intensity. The spacial coherence of the wind fluctuations, although plays an important role on the buffeting responses of the main structure, has no substantial effects on the BIR of the hangers. Finally, replacement of steel strand with CFRP material has been verified as a very effective countermeasure against the BIR of hangers.

국부오손이 옥외절연물의 전기적 특성에 미치는 영향 (Influence upon electrical properties of outdoor insulators with non-uniformity contamination)

  • 이원영;최남호;박강식;한상옥
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2001년도 학술대회논문집
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    • pp.203-206
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    • 2001
  • Since th three sides of korea peninsula are surrounded by the sea, electric apparatus are greatly contaminated by the salt generated by the typhoon, seasonal wind, sea wind and sea fog. This contamination causes electric power apparatus to fail. Thus in this paper, we investigated to influence upon electrical properties of outdoor insulators with non-uniformity contamination in the experimental condition because The contamination of outdoor insulator highly depended wind property In the service condition, insulator was not uniformly contaminated. From the flashover test for the 254 mm suspension insulator, we could determine the influence non-uniform contamination on the electrical property of insulators. Through the experiment, we convinced to occur flashover from non-uniform contamination region of outdoor insulator. Contaminated area and pattern has a close relationship with the electrical properties of outdoor insulator.

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풍력터빈 토크제어의 특성 고찰 (A Study on Properties of Torque Control for Wind Turbine)

  • 임채욱
    • 제어로봇시스템학회논문지
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    • 제15권12호
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    • pp.1157-1162
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    • 2009
  • The aerodynamic torque and power caused by the interaction between the wind and blade of wind turbine are highly nonlinear. For this reason, the overall dynamic behaviors of wind turbine have nonlinear characteristics. The aerodynamic nonlinearity also affects properties of torque control for wind turbine. In this paper, the nonlinear aerodynamic property according to the wind speed below rated power and its effects on the torque control system are investigated. Nonlinear parameter representing change of aerodynamic torque with respect to rotor speed is obtained by linearization technique. Effects of this aerodynamic nonlinear parameter on the closed-loop torque system with PI controller for an 1.5 MW wind turbine are presented.

Non-stationary and non-Gaussian characteristics of wind speeds

  • Hui, Yi;Li, Bo;Kawai, Hiromasa;Yang, Qingshan
    • Wind and Structures
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    • 제24권1호
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    • pp.59-78
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    • 2017
  • Non-stationarity and non-Gaussian property are two of the most important characteristics of wind. These two features are studied in this study based on wind speed records measured at different heights from a 325 m high meteorological tower during the synoptic wind storms. By using the time-frequency analysis tools, it is found that after removing the low frequency trend of the longitudinal wind, the retained fluctuating wind speeds remain to be asymmetrically non-Gaussian distributed. Results show that such non-Gaussianity is due to the weak-stationarity of the detrended fluctuating wind speed. The low frequency components of the fluctuating wind speeds mainly contribute to the non-zero skewness, while distribution of the high frequency component is found to have high kurtosis values. By further studying the decomposed wind speed, the mechanisms of the non-Gaussian distribution are examined from the phase, turbulence energy point of view.

On wind resistant properties of Tiger Gate suspension bridge

  • Xiang, H.F.;Chen, A.R.;Song, J.Z.
    • Wind and Structures
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    • 제1권1호
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    • pp.67-75
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    • 1998
  • Tiger Gate Bridge, a steel suspension bridge with a main span of 888 m and a stiffening box girder, is located at the Pearl River Estuary, Guangdong Province, one of the typhoon-prone area in China. Focusing on the developing of the full aeroelastic model of the bridge and simulation of the wind field of the bridge site in a large boundary wind tunnel at Tongji University, Shanghai, China, some main results about the wind resistant properties of the bridge including aerodynamic instability, buffeting responses both being in operation and erection stages by using of a full aeroelastic model wind tunnel testing are introduced. Some of analytical approaches to those aerodynamic behaviours are also presented, and compared with experimental data of the testing.

제주도 해안마을 울담의 높이에 관한 연구 (Study on Height of Stony Walls in Coastal Villages of Jeju Island)

  • 이성우;김만규
    • 대한지리학회지
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    • 제47권3호
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    • pp.390-406
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    • 2012
  • 제주도 돌담은 최근 들어 문화유적, 관광자원 등으로 주목받으며 지방자치단체 차원에서 다양한 복원사업이 추진되고 있다. 본 연구는 돌담의 물리적인 복원과 함께 돌담의 형성 배경과 의미를 밝히는 것 역시 중요한 일이라 생각되어 진행하였다. 집주변에 울타리를 형성하고 있는 돌담인 울담의 높이를 중심으로 조사를 하였고 바람지도, 지질도, 주민 인터뷰를 활용하여 연구를 하였다. 연구결과, 제주도 해안마을에서는 돌을 쉽게 구할 수 있고, 주민들이 방풍 역할을 주목적 기능으로 울담을 세운 마을의 경우에 최대 풍속이 큰 곳에서 울담이 높게 나타나는 경향이 있다는 것을 확인할 수 있었다.

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Field measurement-based wind-induced response analysis of multi-tower building with tuned mass damper

  • Chen, Xin;Zhang, Zhiqiang;Li, Aiqun;Hu, Liang;Liu, Xianming;Fan, Zhong;Sun, Peng
    • Wind and Structures
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    • 제32권2호
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    • pp.143-159
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    • 2021
  • The 246.8-m-tall Beijing Olympic Tower (BOT) is a new landmark in Beijing City, China. Its unique architectural style with five sub-towers and a large tower crown gives rise to complex dynamic characteristics. Thus, it is wind-sensitive, and a double-stage pendulum tuned mass damper (DPTMD) has been installed for vibration mitigation. In this study, a finite-element analysis of the wind-induced responses of the tower based on full-scale measurement results was performed. First, the structure of the BOT and the full-scale measurement are introduced. According to the measured dynamic characteristics of the BOT, such as the natural frequencies, modal shapes, and damping ratios, an accurate finite-element model (FEM) was established and updated. On the basis of wind measurements, as well as wind-tunnel test results, the wind load on the model was calculated. Then, the wind-induced responses of the BOT with the DPTMD were obtained and compared with the measured responses to assess the numerical wind-induced response analysis method. Finally, the wind-induced serviceability of the BOT was evaluated according to the field measurement results for the wind-induced response and was found to be satisfactory for human comfort.

지리정보를 이용한 풍속지형계수 산정 (Estimation of Topographic Factor of Wind Speed Using Geographic Information)

  • 성민호;박경식;최세휴
    • Spatial Information Research
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    • 제18권3호
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    • pp.13-22
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    • 2010
  • 최근 이상기후로 인한 강풍 및 태풍이 자주 발생하여 많은 인적, 물적 피해가 발생함에 따라 구조물 설계 시 적용하는 풍하중 산정에 관한 연구의 중요성이 강조되고 있다. 지형에 따른 풍속지형계수의 증가는 풍속의 증가를 의미하며 풍속의 증가는 제곱에 비례하여 풍하중에 영향을 미치기 때문에 풍속지형계수 산정을 위한 지리정보를 정확하게 측정하는 것이 필요하다. 따라서, 본 연구에서는 BIM(Building Information Modeling) 프로그램인 ArchiCAD를 이용하여 정확하고 합리적인 풍속지형계수 산정 방법을 제시하고자 한다. 풍하중을 고려한 구조물 설계 시 본 연구에서 제안한 방법을 이용함으로서 설계의 합리성과 경제성을 더 높일 수 있을 것이다.