• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1934-1938
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• 2009

본 연구에서는 과거부터 다양한 형태로 발생한 산사태의 주요 원인을 파악하고 우리나라에서 산사태 발생을 유발시키는 요인과 그 특성을 분석하기 위해 현재까지 발생한 산사태의 붕괴 지역을 조사하고 주요 원인을 강우, 토양, 침투, 경사의 4가지 경우로 나누어 이에 대한 지역별 특성을 조사 분석하였다. 분석방법으로는 지역별 확률 강우량 산정 후, 이를 토대로 침투량과 유출량을 분리하여 경사면에서의 침투거동과 지하수위 변화양상을 살펴보기 위해 SEEP/W를 이용하여 지역별 산사태 붕괴원인을 분석하였다. 그 결과, 일부지역을 제외한 대부분 지역에서 강우량이 증가함에 따라 지하수위가 선형적으로 증가하는 것으로 나타났으며, 이러한 피해형태는 사면의 위치별로 다르게 나타고 있어 지역별로 산사태 붕괴원인에 따른 적합한 대처가 필요한 것으로 분석되었다.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.19-25
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• 2010

Inventory survey is process collecting data about cut slope. It's different from inspection. Collected data are being used get at status about cut slope along national roads. And we analyse between current situation and data about collapse slope. It helps finding better method about maintenance of cut slope. We found changes in the situation between data at present and data at 10 years ago. We will research collapse and counterplan by cause.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.115-123
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• 2007

Recently, accelerating population and advanced economy result in extending old freeways and constructing new freeways. To make a good freeway shape, tunnel constructions are also rapidly increasing. Therefore, a possibility of a collapse during a tunnel excavation is getting higher in a proportionate manner. Especially, tunnel excavation has increased in poor geological condition in order to maintain good alignment of road and the collapse of tunnel has often happened without reinforcement method. This research paper will analyze for ms and causes of the collapses for different geological conditions and applied reinforcement solutions by investigating typical collapse sites during highway tunnel constructions.

• The Journal of Engineering Geology
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• v.4 no.3
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• pp.343-356
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• 1994

When most of the industry and social indirect facilities such as the large structure, power plant or road, rail-road are constructed, the new slope may lead to the slope failure. The failure models for slopes have been developed by using the results of in-situ and laboratory tests to investigate the mechanisms and types of the slope failure. The safety factor of a slope may be obtained based on the proposed model and the slope can be reinforced to meet the design criteria. The slope should be reinforced by using the optimum model that properly reflects the site condition, the method of reinforcement includes the increased safety factor either by decreasing a slope angle or by reinforcing the slope.

• Applied Microscopy
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• v.41 no.4
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• pp.277-284
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• 2011

This study was conducted to determine the antiseptic effect of stabilized chlorine dioxide (S-$ClO_2$) on muscle tissue of rats. Skeletal muscle of 8-week old Sprague-Dawley rats was used. Light and transmission electron microscopic findings were observed in the control group, which was not treated with stabilized chlorine dioxide, and in the experimental group, which was treated with a stabilized chlorine dioxide powder in aqueous solution. According to the LM and TEM observations, the day 1 control group showed the initiation of endomysium collapse resulting in an unclear boundary of muscle fibers, and partial collapse of the mitochondrial membranes. All endomysium had collapsed, and bacteria were observed among muscle fibers in the day 2 and later groups. Shapes of muscles were not distinguishable in day 3 or later groups. In contrast, the day 1 and 3 experimental groups revealed detailed structure of typical muscles, but partial collapse of the mitochondrial membranes was observed in the day 3 and later groups. Subsequently, connective tissues collapsed and structures in the shape of concentric circles were observed. In summary, the day 1 control group showed the initial collapse of tissues, and shapes were not distinguishable in the day 3 and later groups because most of the tissues had collapsed. In contrast, the day 3 experimental group showed partial collapse, but the overall shapes of muscles were maintained as time went on, confirming the antiseptic effect of stabilized chlorine dioxide on muscles.

• Journal of Korea Water Resources Association
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• v.34 no.2
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• pp.155-167
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• 2001

The effects of bank crest width, slope steepness, soil properties, and soil compactness on the characteristics of levee breach due to overlfow were investigated through a series of experiments. Generally, the major factors influencing the breach phenomenon are compactness, soil properties. crest width, and slope steepness, in that order. Using proper soil, and ensuring enough compactness in bank construction are very essential for extending breach duration and reducing peak overflow ranges for the values of breach duration, breach width, width-to-depth ratio, and side slope of the breach section, proposed by Singh, MacDonald and Fread based on the field data for earth dam breaks were reasonable. We found that those criteria could also be applied to the phenomenon of levee breaching.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.220-220
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• 2021

2020년 장마는 6월 중순부터 8월 중순까지 전국적으로 평균 687 mm의 강수가 내려, 1973년 이후 역대 2위 강수량을 기록하였으며, 연이은 태풍으로 큰 인명 및 재산 피해가 발생하였다. 특히, 섬진강 및 한탄천 등에서 계획홍수위를 초과하는 홍수로 인해 상당수의 제방이 월류로 인해 붕괴된 것으로 나타났다. 따라서, 향후 기후변화에 따른 연평균 강수량이 증가할 것으로 전망되는 가운데 집중호우로 인한 제방 붕괴 피해를 최소화하기 위한 고도화된 기술 개발을 통한 선제적 재발 방지대책이 필요한 시점이다. 한국건설기술연구원은 바이오폴리머라는 새로운 친환경 신소재를 이용하여 제방의 안정성 평가 기술 개발 연구를 수행하고 있다. 이에 안동하천연구센터에서는 실규모에 준하는 제방모형(높이 3 m, 사면경사 1:2, 길이 10 m 이상)을 제작하고, 제방 표면에 바이오폴리머 신소재를 처리하여 전방 월류 흐름 유도에 따른 실규모 제방붕괴실험을 수행하였다. 또한, 신소재 보강 및 무보강 조건에 따른 영상분석 기반 붕괴지연효과를 정량적으로 분석하여 신소재의 성능을 평가하였다. 하지만, 기존에 수행된 실험은 댐 붕괴 흐름과 같이 홍수파가 발생하여 제내지로 퍼져 나가는 형태로 진행되어, 보강공법의 검증에 있어 실제 하천에서 발생하는 횡월류 흐름을 재현하지 못한다는 한계를 가지고 있다. 본 연구에서는 횡월류 흐름(0.6 m³/s 이상)을 발생시켜 수리실험에 따른 축척효과(scale effect)를 최소화하고, 현장에 대한 충분한 자연성을 재현하는 것을 목표로 하여 실험을 수행하였다. 실험 조건은 1) 신소재가 처리된 식생 제방, 2) 신소재가 처리되지 않은 식생 제방으로 각각의 조건에 따른 횡월류 흐름 및 제방 붕괴를 유도하여 영상분석 기법(이미지 픽셀분석 및 3D 포인트 클라우드 모델링)을 통한 침식 저항에 관한 분석결과를 제시하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1377-1387
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• 2013

Most embankment of the reservoirs (99.1 %) have been constructed in the earth filled type in Korea because the construction of this type is less expensive and simpler than others such as concrete one. However, it has to be reinforced the slope to prevent the breach due to overtopping or piping under unexpected flood conditions. This study has been analyzed the retardation effect using three types (L, T, $L^*$ shape) of stiffener in order to reinforce embankment when they are collapsed by overtopping flow. Experimental results showed that L-type stiffener is the most effective in delaying the breaching of embankment and reducing the soil erosion when compared with others. The reinforced embankment breaching showed that time delay was occurred about 1.73 to 2.29 times and the peak flowrate was reduced compared to non-stiffener embankments due to energy dissipation by collision and less soil erosion. The embankment breaching mostly leads to major damages because of the lack of repair time. Thus, since these stiffeners can resist the rapid breach, it would be possible to earn the time to emergency repair and lifesaving, as well as reduction of damages of embankment in downward region with decreasing peak flowrate. Results from this study would be used for the basis when establishing the emergency action plan for the reservoirs on the verge of hazard.

• Proceedings of the Korea Water Resources Association Conference
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• 1999.05a
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• pp.669-674
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• 1999

• The Journal of Engineering Geology
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• v.29 no.4
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• pp.541-552
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• 2019

In this study, landslide flume tests were performed to analyze characteristics of ground characteristics and landslide occurrence due to rainfall infiltration. As test materials, weathered granite soil and gneiss soil, the most frequent landslides in Korea, were used, and landslides were triggered by heavy rain (Intensity = 200 mm/hr). The measurement sensors were installed with 3 sets at toe, slope, top part and shallow (GL-0.2 m), middle (GL-0.4 m), and deep (GL-0.6 m) depth in the slope and measured at 10 second intervals. After landslide flume tests, the slope stability analysis was performed by applying the unsaturated soil theory based on the change of ground characteristics and compared with actual landslide occurrence from flume test. As a result of the analysis, factor of safety reflected the landslide occurrence from flume test and factor of safety decreased as rainfall infiltration, leading to slope failure. Finally we compared to the factor of safety below 1 and actual landslide occurrence time, the average difference was 1,600 seconds for weathered granite soil and 5,400 seconds for weathered gneiss soil.