• Journal of the Korean Geosynthetics Society
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• v.2 no.3
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• pp.47-55
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• 2003

This paper presents the two field walls that demonstrate the effect of rainfall on the performance of soil-reinforced retaining wall. A field test wall constructed in Geotechnical Experimental Site at Sungkyunkwan University has been monitored for more than 8 months to study the long-term behavior of soil-reinforced retaining wall. The measured data showed a good correlation between rainfall and wall movement after wall completion. A case of failed soil-reinforced retaining wall also is presented to highlight the effect of rainfall on the performance of soil-reinforced retaining wall. Implications of the findings are discussed.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.89-93
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• 2010

It is well known that the drastic change of hydrological characteristics of an urbanized basin causes severe runoff, sediment yield, and peak flow. High vulnerability of urban flood disasters is caused by land-use change and development of a basin. A typical site suffering urbanization was selected and the experimental site has being operated last three years. Hydrological and hydraulic characteristics of the urbanizing basin were examined by observation of runoff, sediment loads and precipitation with T/M. The effects of land-use change were analyzed by examination of the hydrological characteristics, such as run-off ratio (runoff volume/rainfall volume), sediment yields. Runoff coefficient of rational equation was increased as basin was urbanized. Suspended sediment yields due to a urban development activities were raised almost 10 times compare to undisturbed condition for small runoff less than 1 cms. Meanwhile, no big change could be detected for bed loads.

• Journal of the Mineralogical Society of Korea
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• v.20 no.3
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• pp.213-222
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• 2007

Changes of turbidity and suspended solid concentration of inflow tend to be very similar in Andong and Imha dam, and show significant effect on the amount of rainfall. Concentrations of suspended solid and turbidity in Imha are higher than these of Andogn dam, and Banbyon have higher values than that of Yongjeon stream in Imha dam. There is no difference in size distribution and mineral composition of the suspended particles in Andong and Imha dam. The turbidity-causing materials are composed of vermiculite. illite, kaolinite, quartz and albite. X-ray diffraction analysis shows that turbidity-causing materials are have similar mineralogy between Andong and Imha Dam, but they have different abundance.

• The Journal of Engineering Geology
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• v.20 no.4
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• pp.409-414
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• 2010

In recent years, intensive rainfall has occurred with increasing frequency due to climate change, and has had an effect on slope failure. Such rainfall is intense and occurs repeatedly. During the rainfall, most of the water flows along the slope face, but some seeps into the soil, inducing surface failure of the slope. In this study, the infiltration characteristics of intensive rainfall are analyzed under various conditions to evaluate its effect on slope stability, using the Finite Element Method. As a results of this study, the shorter rainfall period and the more rainfall repetition number, the bigger effect of rainfall infiltration is and although the duration of rainfall is short, infiltration effect of rainfall is necessary to be considered on slope stability.

• Journal of Korea Water Resources Association
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• v.40 no.9
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• pp.743-754
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• 2007

This study theoretically compared three possible methods for the ground-truth, that is three ground-truth designs of radar rainfall using the rain gauge rainfall. Theoretical results derived are first applied to the rainfall field generated by the Waymire-Gupta-Rodriguez Iturbe(WGR) model, and then to the Mt. Gwanak radar data using the rain gauge data from MOCT within the radar range of observation. Overall application results were found to be similar to those from theoretical studies, also those from the application to the WGR rainfall field. In conclusion, the ground-truth design using only positive(+) rainfalls from both radar and rain gauges causes serious design bias to be inappropriate as a ground-truth design.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.369-370
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• 2002

우리나라는 에너지원 다변화정책의 부족으로 인하여 화석연료의 과다사용 현상을 유발하고 있으며, 이로 인한 대기 및 기상환경의 악화현상이 초래되고 있는 실정이다. 또한, 산성비, 산성안개, 광화학스모그, 온실효과 및 사막화 현상의 원인이 되고 있으며, 이로 인한 심각한 환경오염문제를 유발시키고 있다. 한편, 경주 및 주변지역에는 1,000여 년을 지켜온 많은 석조문화재와 다양한 문화유적이 산재하여 있다. (중략)

• Journal of the Korean Geotechnical Society
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• v.35 no.12
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• pp.45-58
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• 2019

In this study, a stochastic analysis procedure based on numerical analysis was proposed to evaluate a kind of intensity-duration rainfall threshold for the initiation of slope failure due to rainfall infiltration. Fragility curves were generated as a function of rainfall intensity-duration from the results of probabilistic slope stability analysis by MCS considering the uncertainty of the soil shear strength, reflecting the results of infiltration analysis of rainfall over time. In the probabilistic analysis, slope stability analyses combined with the infiltration analysis of rainfall were performed to calculate the limit state function. Using the derived fragility curves, a chart showing the relationship between rainfall intensity and slope failure-time was developed. It is based on a probabilistic analysis considering the uncertainty of the soil properties. The proposed probabilistic failure distribution analysis could be beneficial for analyzing the time-dependent failure process of soil slopes due to rainfall infiltration, and for predicting when the slope failure should occur.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.155-163
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• 2010

The flash flood is characterized as flood leading to damage by heavy rainfall occurred in steep slope and impervious area with short duration. Flash flood occurs when rainfall exceeds Flash Flood Guidance(FFG). So, the accurate estimation of FFG will be helpful in flash flood forecasting and warning system. Say, if we can reduce the uncertainty of rainfall-runoff relationship, FFG can be estimated more accurately. However, since the rainfall-runoff models have their own parameter characteristics, the uncertainty of FFG will depend upon the selection of rainfall-runoff model. This study used four rainfall-runoff models of HEC-HMS model, Storage Function model, SSARR model and TANK model for the estimation of models' uncertainties by using Monte Carlo simulation. Then, we derived the confidence limits of rainfall-runoff relationship by four models on 95%-confidence level.

• Journal of the Korean earth science society
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• v.35 no.2
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• pp.115-130
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• 2014

The growing possibility of the disaster due to severe weather calls for disaster prevention and water management measures in South Korea. In order to prevent a localized heavy rain from occurring, the rainfall must be observed and predicted quantitatively. In this study, we developed an adjustment algorithm to estimate the radar precipitation applying to the local gauge correction (LGC) method which uses geostatistical effective radius of errors of the radar precipitation. The effective radius was determined from the errors of radar rainfall using geostatistical method, and we adjusted radar precipitation for four heavy rainfall events based on the LGC method. Errors were decreased by about 40% and 60% in adjusted hourly rainfall accumulation and adjusted total rainfall accumulation for four heavy rainfall events, respectively. To estimate radar precipitation for localized heavy rain events in summer, therefore, we believe that it was appropriate for this study to use an adjustment algorithm, developed herein.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.471-471
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• 2023

소양댐 상류 유역에 위치한 고랭지 밭에서 강우시 많은 양의 탁수가 유입되고 있어 상·하류지역사회에 갈등을 유발하고 하천 환경오염의 주범으로 지목되었다. 이에 환경부는 2007년부터 꾸준히 소양호 유역을 비점오염원 관리지역으로 지정하여 다양한 노력을 기울여왔으나 여전히 소양강 상류 수계의 강우시 흙탕물 발생이 지속적으로 문제가 되고 있다. 특히 고랭지 농업이 활발한 자운지구의 경우 고랭지 밭 경작 이외에도 나대지 상태로 방치되거나, 절삭지 보호가 제대로 이루어지지 않는 등 여러 가지 문제로 토사유출이 심각하게 발생하고 있어 흙탕물 관리가 필요한 실정이다. 이에 본 연구에서는 자운지구를 포함한 내린천 유역을 대상으로 강우유출수 모니터링을 수행하였으며, 모니터링 결과를 바탕으로 강우시 비점오염물질 유출 특성을 분석하였다. 강우유출수 모니터링은 2022년 3월부터 10월 중 총 5회를 수행하였으며, 내린천 유역 내 유량 측정망이 설치되어 있는 4개지점(양지교, 현리교, 하죽천교, 원대교)과 내린천 상류 2개지점(에코빌리지, 새터교) 총 6개 지점에서 강우유출수 모니터링을 실시하였다. 분석된 자료를 바탕으로 각 소유역별 EMC, 오염부하, 단위면적당 오염부하를 산정한 결과 하죽천교와 원대교의 단위면적 당 오염부하가 높게 나타났다. 이는 해당 소유역(내린천 하류)에서 발생한 강우강도가 상류에 비해 높았으며, 하죽천교는 유역내 농경지의 비율이 높고, 원대교는 가파른 경사도의 영향이 큰 것으로 판단된다. 또한, 하죽천교와 원대교 소유역에서 배출된느 흙탕물이 내린천 유역의 하천수질 오염에 상당한 기여를 하고 있는 것으로 나타났으며, 오염 우심 소유역에서 발생하는 흙탕물 저감을 위한 적절한 대책이 마련되어야 할 것으로 판단된다. 본 연구 결과와 같이 장기적인 모니터링을 통해 내린천 유역의 흙탕물 저감 대책 수립을 위한 기초자료로 활용할 수 있을 것으로 기대된다.