• Journal of Wetlands Research
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• v.21 no.spc
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• pp.134-140
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• 2019

In this study, we propose a new method for evaluating the vulnerability to flooding river levee. The purpose of this study is to examine how to apply the factors necessary to calculate the proposed levee flood index. To do this, the safety flood level was analyzed by applying the planned flood level. The levee flood vulnerabilities index was calculated based on seven factors such as freeboard, levee crown section, levee section ratio, safety factor, raised spot length, Seepage line change degree, and critical velocity. The Levee Flood Vulnerability Index(LFVI) of the levee developed in this study was used to levee vulnerability analysis. The results of the analysis were divided into 1 to 7 grades using Levee Flood Vulnerability Index(LFVI).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.341-351
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• 2015

This study is to select the areas to ensure stream space or to implement flood defence measures according to flood frequencies by classifying the stream segment using river bed slope in Mangyeong river. The analysis result for each stream segment showed that the variation of flood inundation area was small in upper stream catchment. But in the lower stream area, the inundation area became larger greatly according to the increase of flood return period. This study classified the catchment of each steam segment as the region of ensuring stream space (ESS), below 10% residential area ratio, and the region of reinforcing flood defence (RFD), over 10% residential area ratio. The analysis results showed that the lower stream area included more RFD regions than upper stream area, and the upper stream area included more ESS regions than lower stream area. In future study, the regions stream spaces can be ensured will be analyzed considering the past stream morphology and the positions of wetlands.

• Korean Journal of Agricultural Science
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• v.48 no.3
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• pp.515-526
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• 2021

The frequency of typhoons and torrential rainfalls has increased due to climate change, and the concurrent risk of breakage of dams and reservoirs has increased due to structural aging. To cope with the risk of dam breakage, a more accurate emergency action plan (EAP) must be established, and more advanced technology must be developed for the prediction of flooding. Hence, the present study proposes a method for establishing a more effective EAP by performing flood and inundation analyses using one- and two-dimensional models. The probable maximum flood (PMF) under the condition of probable maximum precipitation (PMP) was calculated for the target area, namely the Gyeong-cheon reservoir watershed. The breakage scenario of the Gyeong-cheon reservoir was then built up, and breakage simulations were conducted using the dam-break flood forecasting (DAMBRK) model. The results of the outflow analysis at the main locations were used as the basis for the one-dimensional (1D) and two-dimensional (2D) flood inundation analyses using the watershed modeling system (WMS) and the FLUvial Modeling ENgine (FLUMEN), respectively. The maximum inundation area between the Daehari-cheon confluence and the Naeseong-cheon location was compared for each model. The 1D flood inundation analysis gave an area of 21.3 km², and the 2D flood inundation analysis gave an area of 21.9 km². Although these results indicate an insignificant difference of 0.6 km² in the inundation area between the two models, it should be noted that one of the main locations (namely, the Yonggung-myeon Administrative and Welfare Center) was not inundated in the 1D (WMS) model but inundated in the 2D (FLUMEN) model.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.4
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• pp.13-22
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• 2020

Recent abnormal climate has increased the frequent of heavy rains and floods, and over 100 people have been killed in the last decade caused by these. In the midst of severe flood disasters, safety education to learn how to respond and evacuate them has become important. The purpose of this study was to analyze the needs and effective education types for the flood disaster school safety education. This study shows Analysis the current state of school safety education based on the 7 standards of school safety education, especially in disaster safety categories through the survey of secondary school teachers and students. And a desirable form of flood safety education was derived by analysis of awareness of flood disaster safety education and their educational needs. More than 70% of teachers and students hoped for a experience-based flood disaster safety education, they wanted to learn once a year, one hour from a safety education specialist in experience facilities. As for the contents of the training, they wanted to experience evacuation in the event of flood disaster, and also wanted education related to survival swimming. The most necessary thing for the establishment of experience-based disaster safety education was the expansion of experience facilities.

• Water Engineering Research
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• v.5 no.4
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• pp.157-176
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• 2004

This research presents a prototype development and implementation of Decision Support System (DSS) for integrated river basin water management for the flood control. The DSS consists of Relational Database Management System, Hydrologic Data Monitoring System, Spatial Analysis Module, Spatial and Temporal Analysis for Rainfall Event Tool, Flood Forecasting Module, Real-Time Operation of Multi Reservoir System, and Dialog Module with Graphical User Interface and Graphic Display Systems. The developed DSS provides an automated process of alternative evaluation and selection within a flexible, fully integrated, interactive, centered relational database management system in a user-friendly computer environment. The river basin decision-maker for the flood control should expect that she or he could manage the flood events more effectively by fully grasping the hydrologic situation throughout the basin.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.389-393
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• 2010

The Objective of this study was to develop a system for visualizing inundation area by using 1-D numerical model analyzing damage information such as inundation area, facilities, land usages, population, building, loads. In this study, we have reviewed hydraulic models to select a flood model for simulation of discharges, water depths and velocities. The study area is Namhan River from Youngwol to Paldang Dam which had a flood damage on upper and below regions of Chungju Dam by a storm event in 2006. At the first, we developed the DB system base on GIS thematic map, ortho images, cadastral maps to analyze flood damages and support decisions making. Changing the boundary conditions such as discharge at the gauging stations, flood simulations were performed and then damages were extracted from the databases information support system based on 1-D numerical hydraulic model, it is expected to be able to analyze flood damages and support a decision making for reduce flood relate damages. In the future, the system developed in this study could be applied for flood forecasting system of small scaled streams.

• Journal of Environmental Science International
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• v.17 no.9
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• pp.957-968
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• 2008

The purpose of this study is to analyze the characteristics of hydraulic behavior of the natural channel flow according to the temporal classification mode, and thus propose the hydraulic analysis method for future channel design. For analysis, the temporal flow characteristics of the channel section was divided into the steady flow and the unsteady flow. For hydraulic analysis, the HEC-RAS model, which is a one-dimensional numerical analysis model, and the SMS-RAM2 model, which is a two-dimensional model, were used and the factors used for analysis of hydraulic characteristics were flood elevation and flow rate. The flow state was analyzed on the basis of the one-dimensional steady flow and unsteady flow for review. In the unsteady flow analysis the flow rate changed by $(-)0.16%{\sim}(+)0.26%$, and the flood elevation varied by $(-)0.35%{\sim}(+)0.51%$ as compared to the values in the steady flow analysis. Given these results, in the one-dimensional flow analysis based on the unsteady flow the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow. The flow state was analyzed on the basis of the two-dimensional steady flow and unsteady flow. In the unsteady flow analysis the flow rate varied by $(-)0.16%{\sim}(+)1.08%$, and the flood elevation changed by $(-)0.24%{\sim}(+)0.41%$ as compared to the values in the steady flow analysis. Given these analysis results, in the two dimensional flow analysis based on the unsteady flow, the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.58-66
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• 2016

This study aims to estimate the failure probability of concrete gravity dams for their risk analysis under flood situation. To the end, failure modes of concrete gravity dams and their limit state functions are proposed based on numerous review of domestic and international literatures on the dam failure cases and design standards. Three failure modes are proposed: overturning, sliding, and overstress. Based on the failure modes the limit state functions, the failure probability is assessed for a weir section and a non-weir section of a dam in Korea. As water level is rising from operational condition to extreme flood condition, the failure probability is found to be raised up to the warning condition, especially for overturning mode at the non-weir section. The result can be used to reduce the risk of the dam by random environmental variables under possible flood situation.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.2
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• pp.149-158
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• 2008

The parameters of each basin, required for the accurate analysis of flood runoff using Storage Function Model, are estimated. Prior to the estimation, sensitivity analysis and extraction of new regional topographic factors for Han River basin are conducted. Based on the result, the outflow constant of basin model is calculated through regression analysis in relation with pre-flood runoff depth. The storage constant of basin model is derived by the optimum storage constant equation, according to the flood event of each basin. The model using the mentioned parameters was compared with K-Water model of Korea Water Resources Corporation and the model of Han River Flood Control Office, and proved to correspond to the observed hydrograph more.

• Water for future
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• v.10 no.2
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• pp.113-124
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• 1977

Alone the southwesten coast of Korean peninsula, the extensive available arable acreages suited for forming are found in the development of tidal flats in the geographically curved bays with a motable tidal emplitude. It was found that the developments of these tidal flats cover an estimated area more than 276,000ha. In this paper, a flood control system by Pul's Storage Indication Method and Pul's Graphical Method at Return Periods-50 yrs, design rainfall-267mm per 48hrs and design flood-926c.m.s. and at 0.2meter control height above the High Water Ordinary Spring Tide Level (+11.0m) was studied. At the result, the flood demage in the reservoir at Return Periods-50 yrs and the tidal level at H.W.O.S.T.L. were satisfied to the below E.L. 11.20m (Flood Level in the reservoir). Well skilled flood control technique and management and control of draining sluice gate should be required for the disaster prevention from the flood and tide damage.