• Journal of Korea Water Resources Association
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• v.45 no.6
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• pp.583-596
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• 2012

The revetment is a installed structure on the slope of river bank to protect against flowing. Through the design standards of domestic and overseas, the maximum tractive force is calculated and applied to the average concept on the slope of river bank. In the case of calculating the method of permissible tractive force on the slope of river bank, there is a need to consider soil sliding. In this study, suggested the tractive force formulae by section of adhesion that have 0 < ${\Phi}$ < $90^{\circ}$ slope of river bank and installed an open channel of length of 20 m and 2 m wide for calculating permissible tractive force and hydraulic model experimented with changing discharge. According to the results, the calculated permissible tractive force of section on the slope is the largest due to the significant effects of surface roughness of different revetment materials. In addition, the permissible tractive force increased in the presence of vegetation but has no the effect by vegetation density.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.147-153
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• 2008

Tractive forces by flowing water and ship generated waves are items that affect the stability of the low flow revetments among various external forces exerting on those revetments. Bank revetment stability by these external forces is analysed in this study. The study area is the section of the test construction area changing the artificial revetments to ecological revetments in Han river. Tractive forces are computed using the calculated flow velocity using RMA-2 model. The stability is analyzed comparing the calculated tractive forces with permissible tractive forces of the revetments in the study area. The calculated tractive forces at section number 93 is higher than permissible tractive forces in that section, so the section is estimated hydraulically unstable. The calculated tractive forces for the storm of 10th August 2007 are small compared to the permissible tractive forces in all sections. The sections are considered to be hydraulically stable, but have been eroded in some parts. The reason for the erosion is considered to have insufficient time for the plants taking root, and be exerted composite forces such as forces by ship generated waves. Ship generated waves by the excursion boats and small boats called river taxi was calculated. Wave forces by these calculated waves are computed and compared with the supporting forces of the revetment material. The external forces exerted by the ships in Han River on the revetments is very little compared with the permissible supporting forces of the revetments, so the revetments are estimated hydraulically stable. But considering the composite forces are exerted simultaneously, the stability consideration should include these composite forces.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6151-6158
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• 2012

By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. Roughness and shear stress are evaluated by 1 D non-uniform model. After each tests, changes in mat surfaces and sub-soil are evaluated, and from these evaluation, 3 types of mat surface damages and 2 types of sub-soil damages are presented. In the study, the case in which some damages in mat surface don't cause loss of sub-soil, is presented to be in the stable condition. Appling this stable condition and acting shear stresses, permissible shear stresses of vegetation mats are evaluated, and the results show that the reinforced mat with wire netting has more permissible shear stress.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.485-485
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• 2023

지금까지 하천에 적용된 호안 조성 기술은 급격한 홍수로 인해 쉽게 유실 및 파괴되고 수생태계에 악영향을 미치는 단점을 지니고 있다. 따라서 수리적으로 안정성을 강화시키고 환경적으로 무해한 호안 조성 기술개발이 필요하다. 개발기술은 무독성 소재인 바이오폴리머를 활용한 자연 친화적인 호안 조성 기술로써 본 연구에서는 수리적 안정성과 환경성을 검토해 보았다. 개발기술의 수리적 안정성 검증을 위하여 한계유속 및 허용소류력 실험 결과 유속 8.0 m/s, 최대 허용 소류력 67.25 kgf/m² (659.05 N/m²)에서 안정성을 확인하였다. 기존 하천에 적용한 기술보다 치수적으로 안정한 것을 확인하였다. 또한, 식생이탈 실험 결과 유속 8.0 m/s에서 식생 피복 전체 면적의 75~85%에서 식생 이탈이 없는 것을 확인하였다. 개발기술의 환경성 검증을 위하여 시범사업지에 대한 모니터링 결과 수질이 양호하고 점차 식생이 이입, 정착하고 있었으며, 다양한 수서생물이 서식하고 있었다. 개발 기술의 환경성이 양호한 것을 확인하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5956-5963
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• 2013

By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. To evaluate soil loss, Terrestrial 3D LiDAR measurement is conducted and soil loss index are calculated from changes of bed elevation. Quantified evaluation for permissible shear stresses is conducted by graphical method for acting shear stresses and soil loss index. By the results of precision survey, changes of sub soil are limited to local range in stable cases and relatively large changes of sub soil which is similar to natural river bed are detected in unstable cases. From the study, evaluation of permissible shear stresses by ASTM D 6040 is avaliable in the failure mechanism and failure criteria by soil loss index.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.134-134
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• 2019

전 지구적 기후 변화가 진행함에 따라 극심한 강우가 증가하고 그로인해 하천의 유량과 유속이 증가하여 제방의 침식 또는 하상의 여러 변화가 일어나 문제가 되고 있다. 이를 예방하기 위한 국내 하천사업에는 호안공법과 높은 유속의 흐름에서도 유실이 되지 않는 하상재료에 대한 다양한 연구들이 진행되고 있으며, 호안공법을 도입 할 때 유속과 하상재료에 따라 하상변화에 미치는 영향을 파악하고 하상재료의 유실과 직접적인 관계가 있는 허용 유속, 소류력에 대해 평가하고 설계하는 것은 하천설계기준에 있어 매우 중요하다. 본 연구에서는 콘크리트와 같이 수질오염을 유발하지 않는 친환경 신소재를 활용하여 실제 제방과 하상에 사용되고 있는 재료인 모래와 황토를 혼합하여 이용하였으며 유속 6 m/s까지 재현이 가능한 실험실 규모의 무경사고속수로와 실시간 데이터측정 장치를 이용하여 유속과 소류력의 상관성을 분석 및 흐름특성을 파악하고 하상의 재료에 대한 적용성을 검토하며 재료에 대한 유실정도를 평가하였다.

• Journal of Wetlands Research
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• v.15 no.1
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• pp.91-103
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• 2013

In this Research, in order to improve problems of not enough technical validation and structural and hydraulic stability evaluation when nature-friendly revetment block is applied to field, hydraulic stability evaluation according to hydraulic behavior change of porosity soil block for vegetation reinforcement that secures ecological function was reviewed. By selecting object section, numerical analysis and hydraulic model experiments were performed; for numerical analysis, by using 1-dimensional numerical analysis model HEC-RAS and 2-dimensional numerical analysis RMA-2, one-dimensional(1D) and two-dimensional(2D) numerical analysis were performed; by applying Froude's similarity law, reduced-scale hydraulic model experiments according to vegetation existence were performed. In hydraulic model experiment, for validity of experiment result, the result of velocity and tractive force of reduced-scale hydraulic model experiments was converted to prototype so that it can be compared and reviewed under the same condition of one-dimensional(1D) and two-dimensional(2D) numerical analysis result; as a result, it was confirmed that comparatively united result appeared, and by comparing prototype-converted tractive force result with revetment's allowable tractive force coming from an existing research, block's hydraulic stability was suggested.

• Journal of the Korean Geotechnical Society
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• v.31 no.2
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• pp.65-73
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• 2015

The bank revetment work which is conducted on the slope of river bank to protect against flowing water as a geotechnical structure has been applied as an average value of critical tractive force based on domestic and international standard design. Currently, an appropriate evaluation is needed for the hydraulic stability and geotechnical behavior analysis of bank revetments because of the effects of climate change and ambiguous design criterion. This study has compared the critical tractive forces of soil improvement material and conventional materials used for the bank revetment work. Through various experiments, the shear strength of mixtures with soil improvement material was investigated by curing time and mixture ratio. It was found that the critical tractive force of the mixture obtained from a scour test is suitable to the reinforcement of the slope of river bank which has problems such as seepage erosion and scour.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.297-297
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• 2023

최근 친수성, 경관, 생태계 보전 등을 위해 다양한 호안블록의 시공이 이루어지고 있어 호안블록의 수리적 안정성에 관한 관심이 증가하고 있다. 이러한 배경 하에 한국건설기술연구원 안동하천실험센터(이하 센터)에서는 2019년부터 실규모 수로를 이용하여 여러 건의 호안블록 실규모 수리검토 실험을 실시한 바 있다. 본 연구는 그간의 실험 결과를 종합적으로 고찰하고 수리 검토 실험의 현황과 한계점, 그리고 개선 방향을 제언하는데 그 목적이 있다. A1 수로(급경사수로, 하상경사 1/70)에서는 7건(21회), B1 수로(고유속수로, 하상경사 1/7)에서는 2건(6회)의 실험이 수행되었다. A1 수로 실험의 유량-소류력 관계는 1.0 m³/s에서 약 20 N/m²이며, 1.0 m³/s 증가당 약 11 N/m²이 증가하는 관계를 나타낸다. 7건의 실험 결과 30분 이상 지속된 최대 실험 유량은 6~7 m³/s 정도이며, 이는 A1 최대 공급 유량의 75 % 정도로서 안정적인 수준이라고 판단된다. 이 때의 최대 소류력은 75 N/m² 정도로 나타났다. B1 수로는 5 m/s 이상의 고유속 흐름을 발생시킬 수있으며, 2건의 실험 결과 0.5 m³/s에서 약 100 N/m², 최대 4.5 m³/s에서 330 N/m²까지 소류력을 제공하여 실험을 수행한 바 있다. 따라서 A1, B1 수로를 통해 제공할 수 있는 소류력 범위는 10~330 N/m²이지만, 75~100 N/m²는 실험에서 제공된 바 없었다. 한편, 토양유실의 경우 수준측량에 의해 측정되는데, 대부분의 실험에서 Clopper의 토양손실 지수(1.27 cm) 미만의 결과가 발생하였다. 이는 시험체에 따라 여건이 다르기는 하지만, 수리 검토 실험시 3회 실험을 기본으로 하고 있고 호안재료의 침식이 기준 이하로 유지되면서 최대한의 성능을 발휘할 수 있는 소류력 조건을 얻으려는 실험 목적에 부합하도록 조절된 것으로 볼 수 있다. 이러한 실험 결과를 토대로 고려해볼 수 있는 개선 방향은 다음과 같다. 강성 재료가 아닌 연성 또는 친환경적 호안재료의 허용 소류력 범위를 보다 넓게 평가하기 위해 A1 수로가 제공하는 최대 소류력을 높일 필요가 있다. 이를 위해 기본 3회의 실험 외에 추가로 호안블록이 파괴되거나 토양유실 임계치를 초과할 수 있는 실험을 수행함으로써 각 제품의 한계 성능을 평가하는 것이 필요할 것으로 보인다.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.751-754
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• 2008

Recently according to increasing of damage in creeks, it has been needed to develop a close-to-nature creek improvement technique considering flood safety as well as the functions of ecosystem and scenery preservation. In this study, the monitoring on creeks in seven provinces was accomplished to develop the technique applicable to domestic creeks between 2002 and 2007. Although the riparian ecosystem was disturbed, after just finishing the improvement on pilot creeks, the result of monitoring showed that restoration rates of creeks were satisfactory by constructing close-to-nature creek revetments. However it is hard to analyze on restoration and permissible tractive force of each revetments constructed in most creeks, because of insufficient monitoring data. Therefore the feasible study on the close-to-nature creek revetments should be performed in the near future through continuous monitoring on creeks.