• Structural Engineering and Mechanics
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• v.88 no.4
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• pp.311-322
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• 2023

Riverine flood is one of the critical natural threats to river-crossing bridges. As floods are the most-occurred natural hazard worldwide, survival probability of bridges due to floods must be assessed in a speedy but precise manner. In this regard, the paper presents a reliability-based approach for a rapid assessment of failure probability of vulnerable bridge components under floods. This robust method is generic in nature and can be applied to both concrete and steel girder bridges. The developed methodology essentially utilizes limit state performance functions, expressed in terms of capacity and flood demand, for probable failure modes of various vulnerable components of bridges. Advanced First Order Reliability Method (AFORM), Monte Carlo Simulation (MCS), and Latin Hypercube Simulation (LHS) techniques are applied for the purpose of reliability assessment and developing flood fragility curves of bridges in which flow velocity and water height are taken as flood intensity measures. Upon validating the proposed method, it is applied to a case study bridge that experiences the flood scenario of a river in Gujarat, India. Research outcome portrays how effectively and efficiently the proposed reliability-based method can be applied for a quick assessment of flood vulnerability of bridges in any flood-prone region of interest.

• Journal of Korea Water Resources Association
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• v.55 no.1
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• pp.85-97
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• 2022

In this study, a method for an integrated flood risk mapping was proposed that simultaneously considers the flood inundation map indicating the degree of risk and the disaster vulnerability index. This method creates a new disaster map that can be used in actual situations by providing various and specific information on a single map. In order to consider the human, social and economic factors in the disaster map, the study area was divided into exposure, vulnerability, responsiveness, and recovery factors. Then, 7 indicators for each factor were extracted using the GIS tool. The data extracted by each indicator was classified into grades 1 to 5, and the data was selected as a disaster vulnerability index and used for integrated risk mapping by factor. The risk map for each factor, which overlaps the flood inundatoin map and the disaster vulnerability index factor, was used to establish an evacuation plan by considering regional conditions including population, assets, and buildings. In addition, an integrated risk analysis method that considers risks while converting to a single vulnerability through standardization of the disaster vulnerability index was proposed. This is expected to contribute to the establishment of preparedness, response and recovery plans for providing detailed and diverse information that simultaneously considers the flood risk including social, humanistic, and economic factors.

• Journal of Climate Change Research
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• v.1 no.1
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• pp.21-30
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• 2010

In this study, vulnerability of water resources to climate change was assessed in terms of flood, drought and water management. Criteria and indicators were employed for assessing the vulnerability. The criteria used to assess the vulnerability was sensitivity of the study area, the exposure to climate and the adaptability to climate change. These criteria were quantified and standardized using corresponding indicators. Vulnerability of water resources to climate change is assessed to be generally increasing over time. The appropriate watershed scales are the large drainage basin for national level vulnerability assessment and the small drainage basin for local one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5B
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• pp.489-499
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• 2006

The Potential Flood Damage (PFD) is widely used for representing the degree of potential of flood damage. However, this cannot be related with the design frequency of river basin and so we have difficulty in the use of water resources field. Therefore, in this study, the concept of Potential Risk for Flood Damage Occurrence (PRFD) was introduced and estimated, which can be related to the design frequency. The PRFD has three important elements of hazard, exposure, and vulnerability. The hazard means a probability of occurrence of flood event, the exposure represents the degree that the property is exposed in the flood hazard, and the vulnerability represents the degree of weakness of the measures for flood prevention. Those elements were devided into some sub-elements. The hazard is explained by the frequency based rainfall, the exposure has two sub-elements which are population density and official land price, and the vulnerability has two sub-elements which are undevelopedness index and ability of flood defence. Each sub-elements are estimated and the estimated values are rearranged in the range of 0 to 100. The Analytic Hierarchy Process (AHP) is also applied to determine weighting coefficients in the equation of PRFD. The PRFD for the Anyang river basin and the design frequency are estimated by using the maximum rainfall. The existing design frequency for Anyang river basin is in the range of 50 to 200. And the design frequency estimation result of PRFD of this study is in the range of 110 to 130. Therefore, the developed method for the estimation of PRFD and the design frequency for the administrative districts are used and the method for the watershed and the river channel are to be applied in the future study.

• Journal of Climate Change Research
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• v.3 no.1
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• pp.1-12
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• 2012

In order to use as basic data of adaptation, this study focused on a 'Water management vulnerability estimation' in Korea. Vulnerability is estimated dividing into flood mitigation and water resource management. Temporal resolution is 2000 year and the future 2020 year, 2050 year, 2100 year via A1B scenario. Time series data was normalized. Then weight that is gotten through delphi investigation was multiplied. Vulnerability is calculated through this process. In flood mitigation vulnerability, it was estimated to adaptation ability affect relatively biggest influence. In future, some area of Gangwon-do was analyzed that the flood mitigation vulnerability increases. In water resource management, it was estimated to climate exposure affect relatively biggest influence. At 2020 yr, there is a trend toward increased in the Chungcheongbuk-do and DaeJeon, Daegu, some area of Gyeongsangnamdo. Because this study evaluate relative vulnerability of whole country and analyzed spatial distribution, when local government establishes climate change adaptation details enforcement countermeasure, this study can give help to grasp whether should invest more in some field.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.59-62
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• 2008

Scour vulnerability evaluation for shallow foundations was performed to assure bridge safety against scour in the national capital region. The case studies for 26 shallow foundations consisted of site investigation including boring test, bridge scour analysis for the design flood, bearing capacity evaluation of the bridge foundation before and after scour, and comprehensive evaluation of bridge scour vulnerability. Bridge scour vulnerability was determined based on the interdisciplinary concept considering predicted scour depth for the design floods and bearing capacity of foundation as well as dimensions of foundation. Nine of 26 shallow foundations showed the potential future vulnerability to scour with significant decrease in the bearing capacity of foundations due to scour and the remaining 17 were expected to maintain their stability against scour.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.145-155
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• 2014

Since greenhouse gas emissions increase continuously, the authorities have needed climate change countermeasure for adapting the acceleration of climate change damages. According to "Framework Act on Low Carbon, Green Growth", Korean local governments should have established the implementation plan of climate change adaptation. These guidelines which is the implementation plan of climate change adaptation should be established countermeasure in 7 fields such as Health, Digester/Catastrophe, Agriculture, Forest, Ecosystem, Water Management and Marine/Fisheries. Basically the Korean local governments expose vulnerable financial condition, therefore the authorities might be assessed the vulnerability by local regions and fields, in order to establish an efficient implementation plan of climate change adaptation. Based on this concepts, this research used 3 methods which are LCCGIS, questionnaire survey analysis and analysis of existing data for the multiphasic vulnerable assessment. This study was verified the correlation among 7 elements of climate change vulnerability by 3 analysis methods, in order to respond climate change vulnerability in rural areas, Seocheon-gun. If the regions were evaluated as a vulnerable area by two or more evaluation methods in the results of 3 methods' comparison and evaluation, those areas were selected by vulnerable area. As a result, the vulnerable area of heavy rain and flood was Janghang-eup and Maseo-myeon, the vulnerable area of typhoon was Janghang-eup, Masan-myeon and Seo-myeon. 3 regions (i.e. Janghang-eup, Biin-myeon, Seo-myeon) were vulnerable to coastal flooding, moreover Masan-myeon, Pangyo-myeon and Biin-myeon exposed to vulnerability of landslide. In addition, Pangyo-myeon, Biin-myeon and Masan-myeon was evaluated vulnerable to forest fire, as well as the 3 sites; Masan-myeon, Masan-myeon and Pangyo-myeon was identified vulnerable to ecosystem. Lastly, 3 regions (i.e. Janghang-eup, Masan-myeon and Masan-myeon) showed vulnerable to flood control, additionally Janghang-eup and Seo-myeon was vulnerable to water supply. However, all region was evaluated vulnerable to water quality separately. In a nutshell this paper aims at deriving regions which expose climate change vulnerabilities by multiphasic vulnerable assessment of climate change, and comparing-evaluating the assessments.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.331-348
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• 2013

The frequency and intensity of abnormal climate caused by climate change is increasing in Korea. Also, the amount of damage from disaster is increasing rapidly. The research on vulnerability assessment analyzes environmentally, socially and economically vulnerable indicators and is ongoing to reduce the intensity of damage and establish adaptation policies for climate change. Therefore, in this study, we assessed vulnerability using weighting value derived by the regression equation. There are 3 evaluation items : vulnerability assessment for farmland erosion to flood, vulnerability assessment for health to heat wave, vulnerability assessment for forest fire to drought. For this study, indicators for each sectors were selected and spatial data for each sectors were established using GIS program. Results showed that vulnerability to heat wave was more affected by climate factors. On the other hand, vulnerability to flood and drought was more affected by social-economic factors. Then, to analysis efficiency of the regression analysis, vulnerability result was compared between the existing vulnerability research with no weighting applied and the vulnerability research with the influence of weighting value derived by the regression. This study showed that the regression analysis is efficient to provide practical and feasible alternatives in terms of planning climate change adaptation policies and it is expected to be utilized for vulnerability assessment in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.385-393
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• 2016

In this study, we analyzed th Cheonggyecheon watershed for urban flood risk index. SWMM model configuration based on each watershed data. And it was set as the final index calculated indicators related to the humanities, social and environmental. Each indicator was standardized and weighted using the Delphi method. Finally, select the danger area through urban flood risk index. Determined 12 indices according to the hazard and vulnerability. Vulnerability is selected the index divided by three factors. 21 watersheds were analyzed through urban flood risk index. The top of three areas of index is Jeongneung 1, Majang, Pil-dong, each index is 0.533, 0.494, 0.381. The lowest index is soongin 0.216. Urban flood risk index developed in this study can be applied to other regions in Korea for establishing national water resources management plan.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.183-194
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• 2019

In recent years, the risk of external flooding of major national facilities has increased significantly since 2000 due to the increase in local heavy rainfall events. For important domestic national facilities, it is necessary to analyze the risk of external flooding as flooding in major sites due to heavy rain can cause functional paralysis in major facilities and ultimately lead to massive trouble events. In order to manage the safety of main facilities and its related facilities at a high level, it is necessary to analyze the degree of disaster such as flood depth, flood flow rate, flood time and flood intensity when extreme floods (LIP) are introduced. In addition, the degree of vulnerability of these related facilities should be assessed and risk assessments should be reassessed through linkage analysis that combines the degree of disaster and vulnerability. By calculating a new flood hazard curve for the flood depth and flood intensity in major national facilities under the heavy rainfall conditions through this study, it is expected to be a basis for the waterproof design of important SOC facilities, flood prevention function design, advancement of flood prevention measures and procedures and evaluation of flood mitigation functions.