• 물과 미래
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• 제28권6호
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• pp.133-146
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• 1995

본 연구에서는 한강 하류부(팔당댐-인도교) 구간의 하도에 대한 Manning 조도계수를 1차원 부정류 모형인 NETWORK을 이용하여 산정하였다. 전체 구간을 팔당댐-광장, 잠수교-인도교등 두 구간으로 구분하고 과거 홍수사상자료를 이용하여 유량 규모별로 조도계수를 구하였다. 산정된 조도계수를 기존 연구결과와 비교하였으며 조도계수의 변화에 따른 수위의 변화를 검토하였다.

• 상하수도학회지
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• 제21권1호
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• pp.113-122
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• 2007

Experimental studies were performed to investigate speciation and leaching potential of heavy metals(Cu, Cd, Pb Zn, Ni) in ten sediment samples collected from Nakdong River. Acid Volatile Sulfide (AVS) and Simultaneously Extractable Metals (SEM) measurements were used to estimate heavy metals that can be leached under anaerobic conditions. Sequential Extraction Procedure (SEP) and Toxicity Characteristic Leaching Procedure (TCLP) were used to characterize speciation and leaching potential of heavy metals under aerobic conditions. The results show that total concentrations of Cu, Zn and Ni were relatively high in the sediments from points Seongseo industrial complex stream (upper stream) (D), Seongseo industrial complex stream (midstream) (E), Dalseo stream (F), and Nakdong river estuary (J), and that Cd concentrations were higher in all sampling points except for Goriung Bridge (G) and Soosan Bridge (H). SEM and AVS analyses reveal that samples from points Ilsun Bridge (A), Namgumi Bridge (C), and Soosan Bridge (H) have potential of heavy metals leaching, although leachable concentrations are relatively low. The leaching potential of heavy metals in other points was low because of higher concentrations of AVS than SEM. SEP results show that more than 50% of Cu, Zn and Ni were present in residual fraction, which means these metals are less amenable to leaching in anaerobic conditions. On the other hand, more than 50% of Pb and Cd were extracted during the first through third step of the SEP, which means substantial fraction of these metals can be leached upon changing of redox conditions. TCLP tests predict that leaching potential of heavy metals was generally low, which is consistent with the results obtained by AVS and SEM measurements.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.667-676
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• 2005

In this research, the reasonable local scour estimates considered conditions of the bed material and the flow was accomplished on two piers P14 and P17 of Il-san bridge. Especially, the Il-san bridge was located on the lower Han-river where is influenced by the tides of In-chon, and it has hydraulic condition that can cause the bridge piers local scour because of tides at ordinary times, as well as a flood. Therefore, the local scour depth has been presented influenced by the maximum velocity of the flow when a flood after construction and the tides on construction on the basis of the standards of river design and road design, furthermore, the results was made a comparative analysis. According to the results, the local scour depth on the basis of the standards of river design was higher than it on the basis of the standards of road design(SRICOS), and the local scour depth influenced by the maximum velocity of the flow when a flood after construction was determined the final local scour depth of P14 and P17 at the Il-san bridge. It was ascertained that the local scour depth did not exceed the inserted depth of bridge foundation.

• 한국환경보건학회지
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• 제16권2호
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• pp.83-87
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• 1990

This study was carried out to investigate the pollution of heavy metals in soil of seven stations from the upper spot (Yeungchun Dam) of Kumho River to the downstream(Gangchang Bridge). The results obtained were as follows: 1. The content of heavy metals in soil of Kumho River basin was highest at Gangchang Bridge [expresed in $\mu$g/g : Mn(246.0), Cd(1.90), Fe(551.2), Cu(108.2), Zn(86.4), Cr(80.2), respectively]. Whereas, the content of heavy metals expect for Mn, Cu was lowest at Yeungchun Dam [Cd(0.40), Fe(548.0), Zn(30.7), Cr(6.2), respectively] Also, the content of Cr, Zn was increased when the sampling areas are changed from upstream to downstream except for Hayang Bridge, and Hayang Bridge was the diverging point of the heavy metals content. 2. There were relatively correlated between Mn : FE, Cu, Zn, Cr, Fe : Cu, Zn, Cr(0.40 < $\left$\mid${r}\right$\mid$$ < 0.70), and were high correlated between Cd : Mn, Fe, Cu, Zn, Cu : Zn, Zn : Cr(0.70 < $\left$\mid${r}\right$\mid$$ < 0.90). Particularly, there was higest correlated between Cd : Cr, Cu : Cr(0.90< $\left$\mid${r}\right$\mid$$ < 1.0)

• Water Engineering Research
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• 제7권1호
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• pp.21-28
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• 2006

The scouring process is complex and subject to many factors. Recently, experiments for real-time bridge scour monitoring have been active as means for a more reliable scour prediction. Riverbed materials are an important factor in bridge scouring; therefore, an accurate estimation of riverbed material is critical in predicting a scour. As a part of this approach, an ultrasonic sensor, which can not only detect river bottom during floods but can also be installed lose to the underwater structures, was developed. This sensor is able to map the river bottom using an ultrasonic waves with the characteristics of the returning wave, reflected from an object or bottom ground. The reflected wave is unique according to the situations, or materials below. Therefore, it would be possible to identify the consisting materials of a riverbed if we could reveal each characteristic in the received signals. In this study, a preliminary experiment was performed in the laboratory to identify and classify received signals, which is unique to each material. The analysis of this experiment gives the graph, which makes it possible to identify materials of the river bottom through the ultrasonic signals. The proposed graph was verified through a comparison with the actual field data measured in river.

• 한국습지학회지
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• 제13권2호
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• pp.363-375
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• 2011

최근 하수관거 매설과 하수종말처리장 등의 건설로 인해 도시하천의 수질이 크게 개선되고 있으나, 하 폐수 처리시설의 부족으로 하천으로 유입되는 다양한 오염물질은 수중생태계 교란과 적조를 발생시키고 있다. 울산 태화강의 하류부는 하폭이 크고 하상경사가 매우 완만한 감조하천으로써 갈 저수기에는 유속이 매우 느리게 된다. 게다가 약 1.2km 떨어져 있는 2개 교량의 전면기초로 된 교각보호공으로 인해 흐름이 정체되고 오염물질이 퇴적되어, 수년전부터 발생하고 있는 태화강 적조의 원인이 되거나 적조를 활성화 시키고 있다. 본 연구에서는 RMA2모형을 이용하여 두 교량의 교각을 독립기초로 개선하고 흐름을 소통시킬 수 있는 통수단면을 확보했을 때, 수리학적으로 개선될 수 있는 유속과 유량의 변화폭을 모의하였다. 그 결과 유속은 최대 약 103%, 유량은 최대 61% 증가하는 것으로 나타났다. 이는 적조를 직접 소멸시킬 수는 없으나 적조발생을 억제하거나 감소시킬 수 있으며, 오염물질의 퇴적을 막아 적조발생 원인을 근원적으로 제어할 수 있는 것으로 판단된다.

• 한국산학기술학회논문지
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• 제17권9호
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• pp.34-44
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• 2016

본 연구는 소하천을 대상으로 홍수로 인한 교량에서의 유송잡물 집적을 방지하기 위한 저감시설에 대한 실험연구이다. 일반적으로 소하천은 태풍 및 집중호우 시 유송잡물에 의한 구조물 피해가 빈번하게 발생하고 있으나 이러한 피해에 대한 저감대책은 전무한 실정이다. 국외에서는 유송잡물로 집적으로 인한 피해저감시설로 수직분리대방식, 말뚝시설방식, 스위퍼 방식에 대해 소개하고 있다. 이에 본 연구에서는 유송잡물 저감시설 중 스위퍼를 대상으로 실규모 집적실험을 통해 저감능력을 검토하고자 하였다. 스위퍼는 교각전면부에 설치하여 자력회전을 통해 유송잡물을 우회시켜 교각에 유송잡물이 집적되지 않게 만드는 시설이다. 실규모 실험을 위해 소교량 모형을 실물크기로 제작하였으며, 유송잡물 길이와 흐름조건에 따라 스위퍼 설치 전 후 집적실험을 통해 저감능력을 검토하였다. 실험결과 유송잡물의 길이가 길어지거나 유속이 적을 경우 집적률이 높게 나타나는 것으로 나타났다. 스위퍼 설치에서 따른 유송잡물의 집적률은 스위퍼 설치 전에 비해 최소 55%에서 최대 88%의 유송잡물 집적률이 저감되는 것으로 확인되었다. 이러한 결과로 판단할 때 유송잡물 잠재능력이 높은 소하천에 스위퍼를 설치할 경우 유송잡물 집적으로 인한 교량의 안정성 확보 측면에서 유리할 것으로 판단된다.

• 미생물학회지
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• 제20권2호
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• pp.98-104
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• 1982

Detergent-degrading bacteria isolated from the Han River downstream running through the center of Seoul area were identified. Samples were monthly taken from the surface waters at four designated sites from October, 1980 to August, 1981. Isolated strains were characteristically Gram-negative bacteria in all, and they were classified within 18 genera, 43 spceies. The dominant strains of detergent -degrading bacteria were within geneus Pseudomonas. On the regional distribution of detergent-degrading bacteria, Euterobacteriaceae and genus Aeromonas were suddenly increased at the Third Bridge of site 2 and the First Bridge of site 3, and others were almost the same regardless of sites.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.685-693
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• 2002

This bridge was planed to be located in Geuk-rak river at south of Kwangju city. And it is very important to emphasis the beauty of bridge appearance. So Ive adopted unbraced tube arch type those linear beauty is elegance and simple. Actually, foreign bridges similar to this won various prizes for excellence of design. But there is no similar precedent in domestic highway bridge. therefore we intended to certify the security of this bridge through computational analysis. In this paper, approximate introduction of this bridge, design procedure and principal examination item is mentioned.

• 한국환경복원기술학회지
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• 제3권2호
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• pp.35-46
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• 2000

Environmental pollution has become more and more serious in urban areas since industrialization as most streams and rivers were developed heavily because of economic opportunism. Recently river restoration techniques, applied in advanced countries, have been introduced to Korea. But the application of river restoration techniques developed in advanced countries, has a lot of limitations in respect of economic loss during construction, suitability for the domestic situation and the problem of flood control. The method of minimizing the problems must take into consideration these issues, including economic considerations. So from these points of view this study intends to plan ecological river restoration and to create a nature friendly river in the case of the Chungrang river. The subject site is the upper part of Chungrang river, from the Nokchun bridge to Sang-kye bridge, where the ecosystem is well preserved in comparison with other parts of the river. The subject site is divided into 10 sections for plant state investigation. The result of plant-state investigation showed pioneer water plants such as Persicaria thunbergii, Oenanthe jaranica, Rumex crispus. appeared very often. On the basis of the existing plant state, this study has planned an appropriate plant state for the river and has planned for bank protection using a method of construction, which is suitable for natural river. In this study, first of all, it is intended to investigate the plant growth state of Chungrang river and try to plan a particular ecosystem for the river for the purpose of the revival of the natural river.