• Journal of the Korean Geosynthetics Society
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• v.23 no.1
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• pp.49-60
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• 2024

Recently, the frequency and intensity of typhoon-induced wave loading are increasing due to changed marine environments such as climate change. In addition, frequent earthquakes are causing a lot of damage around the world, including in Japan, Chile, Haiti, China, and Indonesia. In Korea, damage from typhoons has also been increasing since the 2000s, and the frequency and intensity of earthquakes are also increasing. Korea is surrounded by sea on three sides, so typhoons can cause a lot of damage to coastal structures, and earthquakes also cause a lot of damage to coastal structures. As such, the frequency and intensity of typhoon-induced wave loading and earthquakes are increasing both domestically and internationally, but there is no research linking typhoons and earthquakes. Therefore, in this study, numerical analysis was performed for a total of four cases by linking typhoon waves and earthquakes to the caisson breakwater. Numerical analysis was performed by applying wave loads in Case 1 and seismic wave in Case 2, seismic wave after wave loads in Case 3, and wave loads after seismic wave in Case 4. As a result of the numerical analysis, it was confirmed that in Case 3 and Case 4, which linked a typhoon and earthquakes, the damage caused by each load increased compared to Case 1 and Case 2 because the load was applied while the existing ground strength was reduced. In addition, it was confirmed that the greatest damage occurred in Case 3, in which seismic wave were applied after the wave loads.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.20-22
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• 2003

This paper focuses on the effects of wind pressure on transmission towers. It recommends the need for an application method to strengthen some existing towers, especially those in areas regularly affected by typhoons, and to be applied to new constructions. Some considerations taken into account were modifying existing towers exposed, which can cause significant damage to the power system and the effects of damage on third parties.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.497-500
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• 2008

The typhoon is provoking huge damage attacking in Korea periodically every year. Therefore, in this study, the analysis of 24 hourly maximum precipitation change related to typhoon events achieved based on Mann-Whitney U test, T test, Modified T test, Sign test, F test, and Modified F test. At the results, the 24 hourly maximum precipitation was expose that average and standard deviation are increasing recently. Therefore, hydorlogical structures have to be prepared of extreme rainfall events by typhoons.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.355-355
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• 2018

Natural hydrology systems, including high flow and low flow events, are important for aquatic ecosystem health and are essential for controlling the structure and function of ecological processes in river ecosystems. Ecosystem responses to flow changes have been studied in a variety of ways, but little attention has been given to how episodic typhoons and atmospheric circulation patterns can change these hydrologic regime-ecological response relationships. In this diagnostic study, we use an empirical approach to investigate the salient features of interactions between atmospheric circulation, climate, and runoff in the five major Korean river basins.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.1
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• pp.1-14
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• 2009

Linear-tracked typhoons were simulated to investigate the effect of parameter sensitivity at Gyeongnam coastal zone. To do this, appropriateness of the linear-tracked MAEMI(0314) was tested and 175 scenarios were simulated on the basis of virtual MAEMI. The results show surge heights are relatively large at Masan and Tongyeong, and it can be attributed to topographical effects. At Masan, 2.5 m-surge height is probable with the same intensity but slightly different track from the real typhoon MAEMI. At the other stations, surge heights induced by real MAEMI are nearly same as the maximum heights of the virtual typhoons, which indicates the real track of the typhoon MAEMI was almost the most severe one. Surge heights caused by the barometric effect are higher than those by the wind effect, and the former effect shows the maximum at the eye of typhoon.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.45-50
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• 2006

About 50% of the population and 75% of the properties concentrate on the flood plain in Japan. The rivers have intimate relationship with our lives. Those conditions have been seen after modern river improvement projects that began about a century ago. The technology which was introduced from foreign countries was improved in conformity with geographical features and the climate condition of our nation, and has redeveloped as a Japanese original technology. In 1940's, Japan had serious natural disasters that were caused by large- scale typhoons. Those typhoons wiped out everything completely. Even though the government realized the importance of flood control and management after those natural disasters, civil work still aimed to economic development. Those construction works have become the one of factors for concentrating population and degrading natural environment in urban areas. Deterioration of river environment has become serious issue in urban development and main cause of pollution. The approaches for environmental restorations which were started about 30 years ago aimed to harmonize with nature environment and cities and human lives. There have been going on many projects called 'river environmental improvement projects', the 'nature friendly river works' and 'natural restoration projects.' The society has tried to find a way to live in harmony with nature. As for societies symbiotic with habitats will form the safe country in the history and the spectacle. Such as the symbiotic of the river or the basin where discharge, water quality, nature, the history, landscape, the local society and also for culture were built in is achieved. Examples of working, applied to restoration technologies and the one to describe the mechanism construction are been shown in the paper. Furthermore, write for an international spread of the river technology of Japan to attempt.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.3
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• pp.309-317
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• 2016

Debris flows are rapidly flowing masses of water mixed with soil and gravel from landslides which are caused by typhoons or rainstorms. The combination of Korea’s mountain dominated topography (70%) and seasonal heavy rains and typhoons causes landslides and large-scale debris flows from June to August. These phenomena often cause property damage and casualties that amount up to 20% of total annual disaster fatalities. The key point to predicting debris flow is to understand its movement mechanism, erosion, and deposition. In order to achieve a more accurate estimation of debris flow path and damage, this study incorporates quantitative analysis of high resolution LiDAR DEM (GSD 10cm) to delineate geomorphic and topographic changes induced by Jinbu real scale debris flow test.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.1
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• pp.49-55
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• 2009

Typhoons are usually influencing at least 3 or 4 times per year in Korean peninsula and they accompanied with strong winds and heavy rains and then brought tremendous loss of properties and lives. Especially typhoon "MAEMI" resulted in a lot of marine accidents of vessels such as sinking, stranding, collision etc. at anchoring or on berthing in pier. If the typhoon comes up to expected area influencing the incidents, the vessel tries to escape from the route of typhoon or anchor in sheltering anchorage. However, consideration of the anchoring or judgement of ship's safety against strong winds is decided only by the experience of operators without detail evaluation of the safety. Therefore, this paper evaluated the safety of T.S. HANBADA by comparing the external forces with the holding powers. Furthermore, based on this evaluation, the anchoring manual was produced for the maximum endurable wind velocity, the general precautions and the actions taken on the ship with steps.

• Structural Monitoring and Maintenance
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• v.1 no.4
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• pp.371-392
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• 2014

Long-span cable-supported bridges are flexible structures vulnerable to unsymmetric loadings such as railway traffic and strong wind. The torsional dynamic response of long-span cable-supported bridges under running trains and/or strong winds may deform the railway track laid on the bridge deck and affect the running safety of trains and the comfort of passengers, and even lead the bridge to collapse. Therefore, it is eager to figure out the torsional dynamic response of long-span cable-supported bridges under running trains and/or strong winds. The Tsing Ma Bridge (TMB) in Hong Kong is a suspension bridge with a main span of 1,377 m, and is currently the world's longest suspension bridge carrying both road and rail traffic. Moreover, this bridge is located in one of the most active typhoon-prone regions in the world. A wind and structural health monitoring system (WASHMS) was installed on the TMB in 1997, and after 17 years of successful operation it is still working well as desired. Making use of one-year monitoring data acquired by the WASHMS, the torsional dynamic responses of the bridge deck under rail traffic and strong winds are analyzed. The monitoring results demonstrate that the differences of vertical displacement at the opposite edges and the corresponding rotations of the bridge deck are less than 60 mm and $0.1^{\circ}$ respectively under weak winds, and less than 300 mm and $0.6^{\circ}$ respectively under typhoons, implying that the torsional dynamic response of the bridge deck under rail traffic and wind loading is not significant due to the rational design.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.53-67
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• 1997

The objective of this study is to provide with the hydro-meteological and probabilistic characteristics of the storms of typhoons that have been passed through the Korean peninsula during the last twenty-three years since 1961. The paths and intensities of the typhoons were analyzed. Fifty weather stations were selected and the rainfall data during typhoon periods were collected. Rainfall data were analyzed for the patterns and probabilistic distributions. The results were presented to describe the areal distributions of probabilistic characteristics. The results obtained from this study can be summarized as follows: 1. The most frequent typhoon path that has passed through the Korean peninsula was type E, followed by types CWE, W, WE, and S. The most frequent typhoon intensity was type B, followed by A, super A, and e types, respectively. 2. The third quartile typhoon rainfall patterns appear most frequently followed by the second, first, and last quartiles, respectively, in Seoul, Pusan, Taegu, Kwangju and Taejon. The single typhoon rainfalls with long rainfall durations tended to show delayed type rainfall patterns predominantly compared to the single rainfalls with short rainfall durations. 3. The most frequent probabilistic distribution of typhoon rainfall event is Pearson type-III, followed by Two-parameter lognormal distribution, and Type-I extremal distribution. 4. The most frequent probability distribution model of seashore location was Pearson type-III distribution. The most frequent probability distribution model of inland location was two parameter lognormal distribution.