접근풍속과 건물 변동풍압력에 대한 연속파동변화법의 적용

함희정 강원대학교 산업기술연구소 2005 産業技術硏究 Vol.25 No.B

Application of proper orthogonal decomposition (POD) and continuous wavelet transform (CWT) is introduced to study wind speed and building roof pressures of flow separation region. In this study, a detailed analysis of the approach wind flow, wind-induced building pressure and the relation between the two fields was carried out using the POD technique and CWT analysis. The results show potential of the application of POD and CWT in characterization of spatio-temporal and spectral properties of the approach wind and its induced dynamic pressure events. Some of findings resulting from the application of this analysis can be summarized as follows: (1) The POD first principle coordinate of the roof pressure in the separated shear layer is closely correlated with the longitudinal component of oncoming flow. (2) The CWT analysis suggests that the extreme peak pressure in the separated shear layer is due to condensed large-scale eddy motions.

방재연구 - 도시 기후.환경 변화 적응을 위한 내풍 방재기술 개발

함희정,Ham, Hui-Jeong 한국방재협회 2013 방재저널 Vol.15 No.4

방재연구 - 도시 기후.환경 변화 적응을 위한 내풍 방재기술 개발

함희정,Ham, Hui-Jeong 한국방재협회 2012 방재저널 Vol.14 No.3

확률 모형 기반의 아파트 창호 시스템 강풍 위험도 평가

함희정,윤우석,최승훈,이승수,김호정 한국전산구조공학회 2015 한국전산구조공학회논문집 Vol.28 No.6

본 연구에서는 강풍 위험과 강풍 취약도의 합성곱을 통하여 강풍 위험도를 평가할 수 있는 확률적 체계를 수립하였으며, 수치적으로 개발한 모형으로 아파트 창호 시스템의 강풍 위험도를 평가하였다. 강풍 위험 모형은 1951년부터 2013년까지에 한반도에 영향을 준 태풍의 기후학적 자료를 몬테카를로 모사기법에 적용하여 개발되었다. 또한 몬테카를로 모사기법으로 창호 시스템의 저항성능과 풍하중의 확률 분포를 비교하여 강풍에 대한 4가지 피해단계의 구조적 파괴확률을 평가할 수 있는 취약도 모형이 개발되었다. 개발된 몬테카를로 모사기법으로 평가한 강풍 위험과 강풍 취약도는 각각 웨이블 분포와 로그정규분포로 곡선맞춤 되었으며, 합성곱을 통한 강풍 위험도 평가에 사용되었다. 본 연구에서 개발한 확률적 위험도 평가체계를 통하여 평가지역, 지표조도, 지형, 지붕 경사각, 건물 높이 등이 아파트 창호 시스템의 강풍 위험도에 미치는 영향성을 정량적으로 평가할 수 있었다. 향후 본 연구를 통하여 개발된 강풍 위험도 평가 모델은 평가지역의 존재하는 건축물에 대한 데이터베이스와 결합하여 손실추정 및 피해 저감대책 수립 등의 분야에서 활용이 가능할 것으로 판단된다. In this study, a coupled probabilistic framework is developed to assess wind risk on apartment buildings by using the convolution of wind hazard and fragility functions. In this framework, typhoon induced extreme wind is estimated by applying the developed Monte Carlo simulation model to the climatological data of typhoons affecting Korean peninsular from 1951 to 2013. The Monte Carlo simulation technique is also used to assess wind fragility function for 4 different damage states by comparing the probability distributions of the window system’s resistance performance and wind load. Wind hazard and fragility functions are modeled by the Weibull and lognormal probability distributions based on simulated wind speeds and failure probabilities. The modeled functions are convoluted to obtain the wind risk for the different damage levels. The developed probabilistic framework clearly shows that wind risk are influenced by various important characteristics of terrain and apartment building such as location of building, exposure category, topographic condition, roof angle, height of building, etc. The risk model presented in this paper can be used as tools to predict economic loss estimation and to establish wind risk mitigation plan for the existing building inventory.

접근풍속과 변동풍압력의 시간 · 공간 · 주기적 특성

함희정,이현호 한국풍공학회 2003 한국풍공학회지 Vol.7 No.1

Application of proper orthogonal decomposition (POD) and continuous wavelet transform (CWT) is introduced to study wind speed and building roof pressures of flow separation region. In this study, a detailed analysis of the approach wind flow, wind-induced building pressure and the relation between the two fields was carried out the POD) technique and CWT analysis. The results show potential of the application of POD and CWT in characterization of spatio-temporal and spectral properties of the approach wind and its induced dynamic pressure events. Some of findings resulting from the application of this analysis can be summarized as follows: (1) The POD first principal coordinate of the roof pressure in the separated shear layer is closely correlated with the longitudinal component of oncoming flow. (2) The CWT analysis suggests that the extreme peak pressure in the separated shear layer is due to condensed large-scale eddy motions. 지붕 가장자리의 바람의 박리지역에서 접근풍속과 변동 풍압력의 시간∙공간∙주기적 성격을 규명하기 위하여 고유직교함수전개법(POD)과 연속파동변환법(CWT)이 본 논문에서 적용되었다. 풍하중의 공간특성과 시간이력을 추출하기 위해서 고유직교함수전개법이 사용이 되었으며, 접근풍속과 변동풍하중의 시간∙주기적 상호관계를 연구하기 위하여서는 연속파동변환법이 적용되었다. 고유직교함수전개 해석을 통하여, 지붕 가장자리의 변동풍압의 첫 번째 고유직교함수전개 모드(mode)에 해당하는 전개계수는 접근풍속의 수평방향 성분과 매우 밀접한 관계가 있음이 밝혀졌으며, 연속파동변환 해석을 통하여 바람의 박리지역에서의 피크풍압은 접근풍속에 존재하는 큰 길이스케일의 와류 운동(large scale eddy motions)과 밀접한 관계가 있음을 알 수 있었다. 결과적으로 변동 풍속과 풍압력의 시간∙공간∙주기적 성격을 규명하기 위하여서 고유직교함수전개법과 연속파동변환 방법이 매우 유용한 것으로 평가되었다.

통계적 축소법을 이용한 미래 풍속의 평가

함희정,이승수,김호정,Ham, Hee-Jung,Lee, Sung-Su,Kim, Ho-Jeong 대한건축학회 2011 대한건축학회논문집 Vol.27 No.12

In this paper, a statistical downscaling methodology is developed to investigate its applicability in downscaling wind speeds over South Korea. The investigation includes calibration of the statistical downscaling model by using large-scale atmospheric variables encompassing NCEP/NCAR reanalysis data, validation of the model for the calibration period, and prediction of the future regional wind speed scenario based on the general circulation model (GCM) outputs of scenario A1B of the CGCM3. Selected as climate variables for downscaling were measured daily wind speed data (1971~2000) from 8 weather stations over South Korea. The results show that: (1) There exists a close relationship between the observed and the simulated daily wind speeds during the calibration period of 1971~2000. (2) Under the scenario A1B, during the prediction period of 2011~2100, effects of climate change influencing on the daily mean and 10 minute maximum mean wind speeds are expected, and these effects are different from region to region over South Korea. (3) However, based on the scenario A1B of the CGCM3, the potential impacts of climate change on the surface wind speed is relatively minor, and the current design wind velocity may not need to be changed for the predicted period.

통계적 축소법을 이용한 한반도 인근해역의 미래 표층수온 추정

함희정,김상수,윤우석 강원대학교 산업기술연구소 2011 産業技術硏究 Vol.31 No.2

Recently, climate change around the world due to global warming has became an important issue and damages by climate change have a bad effect on human life. Changes of Sea Surface Temperature(SST) is associated with natural disaster such as Typhoon and El Nino. So we predicted daily future SST using Statistical Downscaling Method and CGCM 3.1 A1B scenario. 9 points of around Korea peninsular were selected to predict future SST and built up a regression model using Multiple Linear Regression. CGCM 3.1 was simulated with regression model, and that comparing Probability Density Function, Box-Plot, and statistical data to evaluate suitability of regression models, it was validated that regression models were built up properly.

Evaluation of Wind Load Factors for Seven Metropolitan Cities Based on Extreme Wind Analysis

함희정,이승수,판자부슈 수완나메티 한국풍공학회 2014 한국풍공학회지 Vol.18 No.3

In this study, wind load factors were evaluated by using the power of the ratio between the wind speedsfor strength design and allowable stress design. The wind speeds of seven metropolitan cities (ie., Seoul, Incheon,Daejeon, Daegu, Ulsan, Gwangju, and Busan) were selected for this evaluation. For the analysis, annual maximumwind speeds were obtained from the Korea Meteorology Administration (KMA), and all the wind speed data usedin this study were corrected for the condition of 10m in height above flat open terrain by using surface roughnessand topographical effect models. Also, the Gumbel probability distribution was used for the analysis of extreme windspeeds with various return periods. From this analysis, it can be found that the current wind load factor of 1.3specified in Korean building code (KBC) 2009 may not be appropriate for the seven metropolitan cities, and a windload factor of 1.2 may be proper to be used with a nominal return period of 700 years for the wind speed of strengthdesign. It is also proposed in this study that a basic wind speed with a return period ranging from 500 to 1,000years with a wind load factor of 1.0 could be used for strength design. It is necessary to analyze wind load factorsfor all regions of Korea to generalize the results of the current study.

농업시설물에 대한 화산재 취약도 평가

함희정,최승훈,이승수,김호정,Ham, Hee Jung,Choi, Seung Hun,Lee, Sungsu,Kim, Ho-Jeong 한국전산구조공학회 2014 한국전산구조공학회논문집 Vol.27 No.6

본 연구에서는 농업시설물 중 내재해형 비닐하우스와 축사에 대한 화산재 취약도를 평가하였다. 이들 농업시설물에 대한 화산재 취약도를 평가하기 위해 화산재 하중의 확률밀도함수와 대상 시설물 저항성능의 확률밀도함수를 비교하는 해석적 접근법 기반의 FOSM(first-order second-moment) 방법이 이용되었다. 화산재 취약도 평가를 위하여 폭과 높이 그리고 단면 및 재료적 특성이 상이한 6종의 내재해형 비닐하우스와 표준형, 해안형, 산간형으로 구분된 3종의 축사가 사용되었다. 또한 FOSM 방법으로 평가된 내재해형 비닐하우스와 축사의 취약도는 GEV(generalized extreme value) 분포함수의 모수 형태로 최적화된 후 데이터베이스화되었다. 본 연구에서 평가한 화산재 취약도는 백두산 화산분화에 따른 화산재 퇴적에 대한 농업시설물의 위험도 평가를 위하여 활용될 수 있다. This paper presents findings from the assessment of the volcanic ash fragility for multi-hazard resisting vinyl greenhouse and livestock shed among the agricultural facilities. The volcanic ash fragility was evaluated by using a combination of the FOSM (first-order second-moment) method, available statistics of volcanic load, facility specifications, and building code. In this study, the evaluated volcanic ash fragilities represent the conditional probability of failure of the agricultural facilities over the full range of volcanic ash loads. For the evaluation, 6 types(ie., 2 single span, 2 tree crop, and 2 double span types) of multi-hazard resisting vinyl greenhouses and 3 types(ie., standard, coast, and mountain types) of livestock sheds are considered. All volcanic ash fragilities estimated in this study were fitted by using parameters of the GEV(generalized extreme value) distribution function, and the obtained parameters were complied into a database to be used in future. The volcanic ash fragilities obtained in this study are planning to be used to evaluate risk by volcanic ash when Mt. Baekdu erupts.

초고층빌딩 빌딩풍 피해 경감을 위한 법·제도 개선방안 도출

함희정 한국풍공학회 2021 학술대회초록집 Vol.24 No.-