• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.599-606
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• 2015

Damage of landslide due to earthquake covers a considerable part of total damage due to earthquake. Landslide due to earthquake affects direct damage of human lives and structures, and social system can be paralyzed by losing functions of roads, basic industries, and so on. Therefore, systematic and specialized research examining the factors affecting the slope stability by earthquakes should be needed. However, method of evaluation of slope stability problems due to earthquake contains somewhat uncertainty since many soil properties are predicted or assumed. In this study, influences of change of soil properties such as degree of saturation and cohesion value are analyzed in factor of safety and displacement using seismic landslide hazard maps based on GIS. As the degree of saturation increases or cohesion decreases, it is found that seismic landslide hazard area marked with factors of safety or displacements tends to increase. Therefore, to draw more exact landslide hazard map during earthquake, it is necessary to obtain accurate soil property information preferentially from site investigation data in the field.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.215-215
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• 2021

인도네시아 수마트라 지진해일(2004년)과 동일본 대지진(2011년)으로 인해 해당지역에서 막대한 인적·물적 피해가 발생하였으며, 지진해일에 대한 사람들의 경각심은 더욱 커지게 된 계기가 되었다. 반면 우리나라는 지진이 빈번하게 발생하는 국가에 비해 상대적으로 지진해일에 대해 안전하다는 국민들의 인식이 강한 것이 사실이다. 하지만 최근 우리나라에서 크고 작은 지진이 발생(2016년 경주 지진, 2017년 포항 지진 등)함에 따라 국민들은 지진 및 지진해일 안전에 대한 경각심이 높아지고 있다. 또한 한반도 주변에서 지진은 끊임없이 발생하고 있으며, 과거 우리나라는 지진해일로 인한 인명 및 재산피해가 기록된 사례도 존재한다(Cho, 2018). 본 연구에서는 원자력 발전소에서 지진해일에 대한 위험성에 대비하기 위해 지진해일 수치모형 실험을 통해 계산된 지진해일고 결과값에 대해 적절한 확률분포 모형을 개발한 후 각 지진해일 시나리오의 연초과 확률을 분석함으로써, 확률론적 지진해일 재해도 분석(PTHA : Probabilistic Tsunami Hazard Analysis)을 실시하는 것이다. 최종적으로는 연구대상지역의 지진해일 안전성 평가에 기여할 수 있는 검증된 자료를 제공한다. PTHA 분석은 미국(Park and Cox, 2016), 인도네시아(Horspool et al., 2014), 남유럽(Lorito et al., 2014), 일본(Japan Society of Civil Engineers, 2016) 등에서 연구가 활발하게 이루어졌으며 현재도 활발한 연구가 진행되고 있다. 본 논문에서는 먼저, 역사 지진해일 및 우리나라 근해에서 발생가능한 지진원(단층매개변수) 조사, 그리고 지진해일 수치모형실험 case 선정을 위한 파향선추적모형(wave ray-tracing) 수행, 마지막으로 지진해일고의 불확실성을 고려하기 위한 로직트리(Logic-Tree)기법 적용 시 사용하게 될 지진해일 단층매개변수 선정을 위한 지진해일 수치모형 실험 등을 수행한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.155-162
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• 2006

This study presents the seismic risk assesment for an extradosed bridge with seismic isolators of lead rubber bearings(LRB). First, the seismic vulnerability of a structure and then the seismic hazard of the site are evaluated using earthquake data set and seismic hazard map in Korea, and then the seismic risk of the structure is assessed. The nonlinear seismic analyses are carried out to consider plastic hinges of bridge columns and nonlinear characteristics of soil foundation. The ductility demand is adopted to describe the nonlinear behavior of a column, and the moment-curvature curve of a column is assumed to be bilinear hysterestic. The fragility curves are represented as a log-normal distribution function for column damage, movement of superstructure, and cable yielding. And seismic hazard is estimated using the available seismic hazard maps. The results show that the effectiveness of the seismic isolators for the columns is more noticeable than those for cables and girders, in seismic isolated extradosed bridges under earthquakes.

• Journal of the Society of Disaster Information
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• v.17 no.2
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• pp.226-235
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• 2021

Purpose: The risk assessment for earthquakes was conducted in accordance with the current design standard (KBC2016) for the Coalescer facility, which is a major facility of energy storage facilities. Method: The risk assessment for earthquakes was conducted in accordance with the current design standard (KBC2016) for the Coalescer facility, which is a major facility of energy storage facilities. Result: In this study, by statically loading earthquake loads and evaluating the level of collapse prevention of special-class structures, facility managers can easily recognize and evaluate the risk level, and this analysis result can be applied to future facility risk management. Earthquake analysis was performed so that. Conclusion: As a result of analyzing the Coalescer facility according to the current design standard KBC2016, the stress ratio of the main supporting members was found to be up to 4.7%. Therefore, the members supporting Coalescer were interpreted as being safe against earthquakes with a reproducibility period of 2400 years that may occur in Korea.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.48-54
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• 2010

The analysis of the seismic risk of an offshore structure with a control device is presented. First, a probability density function was developed to represent seismic hazard, and seismic fragility under artificial earthquake conditions was determined. Fragility curves for an offshore structure with both passive and active control devices were determined. Displacement criteria were set to evaluate the performance of the structure. Based on numerical analysis, the seismic risk to the structure was considerably reduced when the structure had a seismic control device. The seismic risk to the actively controlled structure was decreased by 80% compared to the uncontrolled case. Reasonable performance evaluations of offshore structure with control devices can be conducted through risk analysis.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.117-130
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• 1999

Earthquakes damage roadway bridges and structures, resulting in significant impacts on transportation system Performance and regional economy. Seismic risk analysis (SRA) procedures establish retrofit priorities for vulnerable highway bridges. SRA procedures use average daily traffic volumes to determine the relative importance of a bridge. This research develops a cost-effective transportation network analysis (TAN) procedure for evaluating numerous traffic flow analyses in terms of the additional system cost due to failure. An important feature of the TNA Procedure is the use of an associative memory (AM) approach in the artificial intelligence held. A simple seven-zone network is developed and used to evaluate the TNA procedure. A subset of link failure system states is randomly selected to simulate synthetic post-earthquake network flows. The performance of different AM model is evaluated. Results from numerous link-failure scenarios demonstrate the applicability of the AM models to traffic flow estimation.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.6
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• pp.47-53
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• 2008

This research focuses on the issue of seismic retrofit prioritization based on the Caltrans' highway network serving Los Angeles and Orange counties. Retrofit prioritization is one of most important problems in earthquake engineering, and it is a problem that most decision makers face in the process of resource allocation. This study demonstrates the methods of prioritized resource allocation in the process of retrofitting a regional highway network. For the criteria of a retrofit ranking, seismic vulnerability and the importance of network link are first introduced. Subsequently, link-based seismic retrofit cases are simulated, investigating the effects of the seismic retrofit in terms of seismic performance, such as driver's delay. In this study, probabilistic scenario earthquakes are used to perform a probabilistic seismic risk analysis. The results show that the retrofit prioritization can be differently defined and ranked depending on the stakeholders. This study provides general guidelines for prioritization strategy for the effective retrofitting of a highway network system.

• Journal of Korean Society of Disaster and Security
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• v.12 no.1
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• pp.45-56
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• 2019

In this study, the seismic risk has been evaluated by setting the bedrock acceleration to 0.154g which, was taking into consideration that the earthquake return period for the buried electric power tunnels in the metropolitan area to be 1,000 years. In this case, the risk assessment during the earthquake was carried out in three stages. In the first stage, the site classification was performed based on the site investigation data of the target area. Then, the LPI(Liquefaction Potential Index) was applied using the site amplification factor. After, candidates were selected using a hazard map. In the second stage, risk assessment analysis of seismic response are evaluated thoroughly after the recalculation of the LPI based on the site characteristics from the boring logs around the electric power area that are highly probable to be liquefied in the first stage. The third Stage visited the electric power tunnels that are highly probable of liquefaction in the second stage to compensate for the limitations based on the borehole data. At this time, the risk of liquefaction was finally evaluated based off of the reinforcement method used at the time of construction, the application of seismic design, and the condition of the site.

• The Korean Journal of Applied Statistics
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• v.13 no.2
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• pp.247-263
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• 2000

Natural catastrophe is defined as all damages caused by natural phenomenon such as typhoon, flood, inundation, windstorm, tidal wave, tremendous snowfall, drought,earthquake and to on It is classified at a huge hazard because of the large severity ofdamage In Korea, Fire Insurance policy includet the coverage clauses and rates of naturalcatastrophe like'Flood , Inundation Coverage Clause'and'Earthquake Coverage Clause'These clauses and rates do not reflect accurate risk of flood, inundation and earthauakein Korea. because those are tariff from other countries Hence, we determine the claimsize distributions and the rates for typhoon coverage and flood-inundation coverage byusing statistical methods which have not been used so far in Korean non-life insurance,and calculate appropriate premium for policyholder's interest

• Journal of Digital Contents Society
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• v.19 no.5
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• pp.899-906
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• 2018

In the entire process of disaster management, it is very significant to construct related information as well as perform quantitative assessment of damage losses with respect to minimizing the effect of disasters. Many countries have paid much attention not only to studying risk assessment methodologies including constructing inventories, hazard mapping, vulnerability assessment and direct/indirect damage loss estimation, but also to developing risk analysis tools investigated in this paper. We conducted comparison studies of representative earthquake damage risk analysis tools, and the result of this study is able to provide useful information to decision makers and researchers who can contribute to development of effective disaster management.