• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.316-320
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• 2002

폭풍해일이나 파랑에 대한 보다 정확한 예측을 위해서는 해상에서의 바람장에 대한 정확한 추산이 선행되어야 하며, 특히 해상ㆍ연안재해를 유발시키는 최대풍이 주로 태풍상황에서 발생되기 때문에 이에 대한 정확한 예측이 매우 중요하다. 태풍은 일반적인 온대성 저기압이나 고기압과는 달리 그 중심부근에서 기압과 바람의 시공간적 변화가 크고 태풍의 중심이 빠른 속도로 이동되기 때문에 일반적인 기상자료 분석에 의해 산출된 바람장은 해양모델에서 요구되는 상세한 변화를 나타내지 못하고, 특히 실제 관측된 기상자료가 전무한 해상으로 태풍이 이동했을 경우에는 일기도 격자점 상의 기압으로 해상풍을 구하는 것은 큰 오차를 유발한다(해양수산부, 2001). (중략)

• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.114.1-114.1
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• 2010

본 연구에서는 우리나라에 적합한 재해예측모형을 구축하기 위하여 중해상도(10km)의 입력 자료를 이용하여 태풍에 의해 지상에 발생 가능한 3-second gust를 추정하였다. 중해상도 입력자료의 구축은 경상남도(부산광역시 포함) 시 군 구 단위의 행정구역으로 구분하였으며, 추정된 3-second gust를 이용하여 건물의 주요구성 요소별로 피해 확률을 구한 뒤, 발생 가능한 최대피해액을 산정하였다. 태풍 Maemi에 의한 최대강풍 피해액은 여러 주택유형 중에서도 '대표주택' 유형의 경우 약 6천억 원으로 분석되었다. 비교적 내륙에 위치한 지역에서는 적은 피해액을, 해안가에 위치한 지역에서는 많은 피해액을 나타내며, 부산광역시에서 피해액이 높은 구 군의 경우 경상남도 시 군의 평균적인 피해액과 비슷한 것으로 보아 부산이 경상남도와 비교하여 면적으로는 작지만 태풍에 의한 강풍에 매우 취약함을 알 수 있다.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.283-286
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• 2008

There were two transmission tower collapses due to Typhoon 'Maemi' in 2003. The reason that a collapse was happened was excessive wind load. One was buckled in the leg part and the other was buckled in the middle bracing part. To investigate a steel transmission tower failure mechanism, 2nd order nonlinear analysis should be performed. Considering the effect of initial imperfection and theresidual stress of angle section during nonlinear analysis, this study can estimate the ultimate strength and the ultimate behavior of the transmission tower.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.705-708
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• 2005

In the case that construcion period is delayed because of the force majeure such as a typhoon or a flood, the owners in general should compensate the damages caused by those. But with exception the weather worsening of ordinary level is paid by contractors, while that of exceptional level by the owners. It is critical that it is difficult to distinguish objectively between ordinary and exceptional level weather worsening. Although the term of "ordinary" itself is too abstractive, we can reduce the disputes between owners and contractors by setting the appropriate and objective standard of distinction. For example in the case of rainfall it may be the standard of distinction whether the days of actual rainfall exceed those of average rainfall or not. If the days of actual rainfall don't exceed those of average rainfall contracters should pay the damages because it is distinguished with a ordinary level weather worsening. Besides the standard of distinction in another weather worsening such as severe cold/hot, strong wind etc. which have a effect on delaying the term of works could be settled as a similar model.

• Journal of Energy Engineering
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• v.29 no.3
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• pp.97-102
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• 2020

In this study, one-way fluid structure interaction analysis was adapted to verify the durability of the outdoor evacuation stair structure operated in the event of a fire when wind pressure caused by a typhoon was applied. To this end, flow analysis was performed with the flow field around the structure of the evacuation stair in a steady state, and the durability was analyzed through structural analysis such as structural stress, deformation, and fatigue life using these analysis results by fluid data input data for structural analysis. As a result of flow numerical analysis, the air flow was different according to the shape of the evacuation stair structure, and this flow velocity distribution generated by the total pressure on the structure surface. Through the structural analysis results calculated by this total pressure, the safety factor calculated as the maximum stress value was found to be more than the safety factor, and durability was proven by fatigue life and deformation analysis.

• Wind and Structures
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• v.12 no.6
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• pp.479-504
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• 2009

Structural health monitoring (SHM) systems have been recently embraced in long span cable-supported bridges, in which buffeting-induced stress monitoring is one of the tasks to ensure the safety of the bridge under strong winds. In line with this task, this paper presents a SHM-oriented finite element model (FEM) for the Tsing Ma suspension bridge in Hong Kong so that stresses/strains in important bridge components can be directly computed and compared with measured ones. A numerical procedure for buffeting induced stress analysis of the bridge based on the established FEM is then presented. Significant improvements of the present procedure are that the effects of the spatial distribution of both buffeting forces and self-excited forces on the bridge deck structure are taken into account and the local structural behaviour linked to strain/stress, which is prone to cause local damage, are estimated directly. The field measurement data including wind, acceleration and stress recorded by the wind and structural health monitoring system (WASHMS) installed on the bridge during Typhoon York are analyzed and compared with the numerical results. The results show that the proposed procedure has advantages over the typical equivalent beam finite element models.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.109-122
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• 2012

Topographic changes in the foredune in Sohwang-ri, Boryeong, Chungnam Province was analyzed over the last two years. Seven cross-sections and one permanent plot ($20m{\times}50m$) were periodically studied based on erosion and deposition measurement, in addition to vegetation monitoring and measurement of wind using an automatic weather station. The sand dunes usually grew from late winter to spring and the growth occurred in a period of strong northwesterly winds. From March to April, heavy sedimentation was observed on the front section of the foredune and sand piled up to ca. 30cm to the ca. 25m landward from the high tide line. It is likely that increased wind force and growth of vegetation played a major role in transportation and sedimentation of sand. Meanwhile, the lower part of the sand dunes was eroded when typhoon and spring tide caused a rise in sea level. The transition zone of beach and dune was usually affected by sea water but some frontal slopes were entirely influenced, resulting in dune scarps. The eroded scarps were naturally restored to their original state as time passed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.3
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• pp.97-109
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• 2010

This study analyzed stratification and destratification processes in the Kangjin Bay (KB), South Sea, Korea, driven by the Nam Gang Dam water discharge based on numerical modeling experiments. Model performances were evaluated in terms of skill scores for elevation, velocity, temperature and salinity, with scores mostly exceeding 90%. The models reproduced the tidal current, density-driven and wind-driven current. The stratification by fresh water input and destratification by the wind mixing was assessed in terms of the characteristic Richardson number (Ri) in that Ri increased from 0 to 7~20 during the Dam water discharge period, while vertical mixing and destratification followed by the typhoon passage showed Ri, 0 to 2.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.3
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• pp.137-152
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• 2004

The climatological characteristics of coastal zone over the southwestern coast of Korea peninsula were investigated using the data observed by AWS (automatic weather system) and 4 buoy points. Coastal zone is climatologically defined as the region bounded by the distinct contrast of temperature gradient and wind speed across coastline. In the southwest of peninsula four cross-lines consisted of AWS aligned with each buoy were selected as Geojedo buoy line, Geomundo buoy line, Chilbaldo buoy line and Dukjukdo buoy line. Analysis on the diurnal cycle and intra-month variation, monthly mean and maximum value, the temperature gradient with distance between buoy and each station and the accumulative frequency of wind speed were applied to find out the characteristics and the range of coast zone. The maximum ranges of coastal zone vary from offshore to Sanglim (about 34 km distance from coastline) for Geojedo buoy line, to Sunchun (about 52 km) for Geo-mundo buoy line, to Jaeundo (about 27 km) for chilbaldo buoy line and to Yongin (about 65 km) for Dukjukdo buoy line. The modification of coastal zone according to synoptic flow was investigated for the onshore, off-shore and calm cases. The ranges of coastal zone are significantly changed with the distance between 65∼90 km for the case of onshore. In addition, we tried to find out the variation of the wind and temperature and the wind ratio of wind speed at ocean to land stations along Geojedo buoy line during 12∼13 Sep. 2003 affected by typhoon (MAEMI).

• Journal of the Korean earth science society
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• v.29 no.3
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• pp.263-279
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• 2008

This study is concerned with the optimization of models using MM5 and WRF mesoscale numerical models to simulate strong sea surface winds, such as that of typhoon Shanshan on 17 September 2006, and the Siberian high event on 16 December 2006, which were selected for displaying the two highest mean wind speeds. The model optimizations for the lowest level altitude, physical parameters and horizontal resolution were all examined. The sea surface wind values obtained using a logarithmic function which takes into account low-level stability and surface roughness were more accurate than those obtained by adjusting the lowest-level of the model to 10 m linearly. To find the optimal parameters for simulating strong sea surface winds various physical parameters were combined and applied to the model. Model grid resolutions of 3-km produced better results than those of 9-km in terms of displaying accurately regions of strong wind, low pressure intensities and low pressure mesoscale structures.