• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.203-206
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• 2008

There are lots of the narrow pass on alluvial channel of Korea. Most of research about this narrow pass of channel were focused on incremental effect of water level at backwater segment. In the meantime this research showed that it is important to valuate the river-bed variation at backward and forward around narrow pass. The sediment deposit at not only the backward of narrow pass but also the forward affected incremental effect of water level. The sediment deposit at the forward of narrow pass headed by sediment that passed through the narrow passed or scoured right around it.

• 한국물환경학회지
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• 제29권6호
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• pp.813-824
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• 2013

In this study, sediment pass-through (SPT) from the Sangju Weir and Gumi Weir in the Nakdong River is analyzed numerically using CCHE2D. Sediment delivery is analyzed to predict the sediment discharge rate in the Sangju Weir and Gumi Weir. The sediment discharge from the Sanju Weir is 4,381 tons in the inflow of $3,857m^3/s$, which are 2 year frequency discharge, for 48 hours, and the sediment discharge is 2,766 tons in the inflow of $1,500m^3/s$. The maximum sediment delivery occurs in the immediate downstream of the weir. The sediment discharge from the Gumi Weir is 3,216 tons in the inflow of $5,400m^3/s$, which are 2 year frequency discharge, for 48 hours, and the sediment discharge is 73 tons in the inflow of $3,857m^3/s$. The maximum sediment delivery occurs in the weir. Therefore, the effectiveness of sediment delivery is high in the condition of the 2 year frequency discharge and the gate in the weirs fully are opened.

• 상하수도학회지
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• 제26권4호
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• pp.503-512
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• 2012

In Yongwon channel, its natural flow of seawater is blocked by the construction of Busan New Port including the container berth. The channel was transformed into a narrow and long one, where it is possible that ships are only allowed to pass through the north-side channel of Gyeonmado located at the point of river mouth to Songjeongcheon. In addition, Yongwon channel is approximately 100 m wide on average and 3,600 m long, and has the highest slenderness ratio (length/width = 36). So it is considered that the changes in the terrain characteristics of Yongwon channel is likely to alter the circulation of sea water, thereby changing its water quality. In this study, the bottom sediment were collected from the 48 points of the Yongwon channel and the long-term leaching characteristics were analyzed. Thus, changes in sediment and water quality were analyzed through the sediment release test to investigate the degree of contamination. The sediment release from the inside region was higher than the outer region, which is due to the pollutant that comes form the downtown area. The results of this study can be used to predict the water quality in the future and prepare the economically optimized countermeasures to improve the water quality of Yongwon channel, Busan New Port.

• Environmental Engineering Research
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• 제18권4호
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• pp.259-265
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• 2013

This study was conducted June 2011 at Gamo Lagoon, after tsunami of March 2011, to estimate food sources and utilization. The results show that the tsunami affected the sediment properties by changing the physical environmental alterations. The fatty acids of the gut content of Nuttallia olivacea mostly comprised the same organic matter found in the sediment. Fatty acids in the tissues showed mainly diatoms, bacteria, and dinoflagellates. That is, most of the food sources (i.e., diatoms, bacteria, dinoflagellates, macroalgae, and terrestrial organic matter) probably pass through the digestive system unharmed; however, terrestrial organic matter, which is refractory to biochemical degradation, indicated a different assimilation trend between the gut content and the tissue. This result suggests that input of labile organic matter from the sediment may control selective metabolism in N. olivacea. From these results, although the physical environment of sediment characteristics by tsunami changed, the food utilization of N. olivacea suggested a better assimilation of selected components from the gut content, irrespective of physical alteration.

• 한국지형학회지
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• 제26권1호
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• pp.41-57
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• 2019

The grain size characteristics of river sediments and the characteristics of bedrock were investigated for the 24km section of the Dong River upstream of the Han River. The bedrock of the study area is various limestone belonging to the Paleozoic Choseon limestone group, and Mesozoic sandstone and conglomerate occur in some areas. Most of the river channel is made of limestone, and most of the river bottom is covered with fluvial sediments. More than 70% of these sediments are sandstone and conglomerate, rather than limestone which forms the basis of the valley. Sediment particles seem to have been supplied upstream of the study area rather supplied from the slope near of the channel. It is difficult to find the statistically significant difference in the shape of the sediment particles of limestones and non-limestones. However, limestones has platy forms rather than block forms, it can be assumed that the limestone was supplied from the surrounding valley wall and transported over a short distance. The particle sizes of DG1~DG2(the upstream section) are decreasing in the downstream direction. However, at DG3, which is a tributary, Jijangcheon, confluence particle size increases and at DG4 particle size increases more. In the case of DG4, it may be influenced by the influx of tributaries, but it also can be supposed as the impact of the large flood in 2002. In the downstream parts(DG5~DG7), the particle size decreases exponentially with distance. The rebound strength of stream sediments and bedrock was measured by using Schmidt hammer. Limestone showed lower rebound strength than non-limestone. According to the results of the sediment and bedrock, it can be seen that the sandstone and conglomerate with high rebound values pass through valley with the relatively low strength limestone. The sediments of limestone were decreased in grain size more rapidly than those of limestone sediments.

• 한국수자원학회논문집
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• 제42권4호
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• pp.319-329
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• 2009

홍수피해를 경감시키고 홍수조절을 목적으로 계획되는 홍수조절용댐의 경우 홍수 발생 기간 외에는 상류와 하류 하천간의 흐름 차단을 억제하고 상류로부터 유입되는 유사가 댐 상류 부분에 퇴적되는 현상을 방지하기 위해 댐에 상시 개방되어 있는 배사관을 설치하기도 한다. 국내에서는 임진강 유역의 홍수피해 저감을 위해 건설되는 한탄강홍수조절댐에 배사관과 생태통로를 설치하도록 계획되었다. 본 연구에서는 1차원 HEC-6 모형을 이용하여 한탄강홍수조절댐 건설로 인한 댐 상류의 퇴사현상을 댐 건설 전의 현상과 비교 분석하였으며 연평균유량 조건뿐만 아니라 연간 유량변동을 고려한 대표유량수문곡선을 적용하여 퇴사현상을 모의하였다. 수치모의 결과, 댐 건설로 인한 하류단 수위 변화가 발생하더라도 하상변동의 영향은 댐에서 상류 2 km 구간을 넘지 않는 것으로 나타났다. 또한 댐 건설 후 배사관의 설치 유무에 따른 배사관 주변과 댐 상류 하상 변화를 예측하기 위해 2차원 RMA2 및 SED2D 모형을 이용하였으며 한탄강홍수조절용댐의 댐 저부에 설치된 배사관의 배사효과는 저수지 내의 퇴적고를 저감시키는 효과가 있는 것으로 나타났다.

• 대한토목학회논문집
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• 제37권3호
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• pp.541-547
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• 2017

용원해역은 부산신항 개발사업의 일환으로 추진된 북컨테이너부두 조성사업 및 항만 배후단지 조성사업으로 전면 해역이 매립되어 원활한 해수흐름이 차단되고 송정천 하구 지점의 견마도 북쪽 통로를 이용한 선박이동만이 가능한 좁고 긴 수로형태로 변형되었다. 따라서 용원수로에 유입되는 오염물질은 수로에 체류되어 서서히 확산되는 양상을 보일 것으로 판단된다. 본 연구에서는 용원수로 내 준설 전 후 퇴적토 용출실험을 실시한 결과 준설 후에 용출농도가 낮게 나타났으며, 그룹별(A~C) 삭감률을 산정한 결과 T-N의 삭감률은 4.6%, 18.0%, 18.6%로 나타났다. T-P의 삭감률은 24.8%, 24.2%, 44.1%로 나타났다. COD의 삭감률은 18.6%, 19.8%, 38.1%로 용원수로 내 준설 후 수질개선의 효과가 나타났으며, 준설을 통한 용원수로 내 오염원을 제어하기 위한 기초자료로 활용하고자 한다.

• 한국해양학회지:바다
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• 제3권2호
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• pp.59-70
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• 1998

가로림만 조간대 표층퇴적물의 입도조직변수(평균입도, 분급도 및 왜도)를 기초로 '이차원 퇴적물 이동벡터모델'을 이용하여 퇴적물의 이동방향을 추정하였고 이에 따른 퇴적물의 이동현상을 해석하였다. 채취된 퇴적물은 각 정점마다 전체와 조립질(< 4.5 ${\phi}$)로 구분하여 각각의 퇴적물이동방향(15 경우)을 구하였고, 이 방향과 지형, 층면형태(bedform)의 정밀측정, 그리고 여러 번의 현장관찰을 기초로 결정된 퇴적물의 실제이동방향과 비교하였다. 퇴적물의 실제이동방향과 가장 일치하는 이동벡터는 조립질 퇴적물에서 퇴적물 이동방향으로 퇴적물이 세립해지고, 분급이 좋아지며 왜도가 감소하는 경우와 퇴적물이 조립해지고, 분급이 좋아지며 왜도가 증가하는 경우를 조합한 M 경우이다. 이는 조립질 퇴적물이 연구지역의 퇴적물이동에 주요 구성성분이며, 세립질(> 4.5 ${\phi}$)을 포함하는 전체 퇴적물보다 퇴적기작이 더 단순하므로 '퇴적물이동벡터모델'과 잘 부합하는 것으로 보인다. 또한 전체 퇴적물과 조립질 퇴적물 모두 퇴적물의 이동방향으로 분급도가 좋아지는 경향이 뚜렷한데, 이는 퇴적기작의 복잡성과 관계없이 연속적인 수리에너지는 퇴적물의 분급을 더 좋게 한다는 것을 증명한다. 또한 이 연구결과를 통하여 사주조간대의 조립질퇴적물의 이동은 남북방향으로 놓여 있는 만 입구 동주수로를 통하여 저조선에서 상부조간대로 이동하면서 퇴적되었고, 일부는 동주수로를 지나 남수로로 공급되어 반시계방향으로 돌며 북쪽지역으로 이동 퇴적되었음이 밝혀졌다. 조립질 퇴적물은 사주에 퇴적되지만, 일부는 북수로를 따라 썰물때 다시 만밖으로 나가는 것으로 퇴적물이동벡터모델이나 퇴적물 실제이동방향의 관찰 모두에서 증명되었다. 따라서 북수로 및 북동쪽 뻘질모래지역은 만 밖에서 운반된 부유퇴적물과 조립퇴적물이 동시에 퇴적되는 지역이며, 지역적으로 조립질과 세립질의 분리퇴적현상이 때때로 관찰되기도 하는 수리역학적 퇴적물 혼합지역이다. 사주의 육지이동과 북수로 발달현상은 조립퇴적물이 만 밖이나 만 입구 등 근원지(장안퇴를 포함한 사퇴)로부터 더 많이 유입되었거나 혹은 상대적 해수면의 상승의 결과로 보인다.

• 상하수도학회지
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• 제27권2호
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• pp.185-196
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• 2013

In Yongwon channel, its natural flow of seawater is blocked by the construction of Busan Newport including the container berth. The channel was transformed into a narrow and long one, where it is possible that ships are only allowed to pass through the north-side channel of Gyeonmado located at the point of river mouth to Songjeongcheon. In addition, Yongwon channel is approximately 100 m wide on average and 3,600 m long, which has the highest slenderness ratio (length/width=36). So it is considered that the changes in the terrain characteristics of Yongwon channel is likely to alter the circulation of sea water, thereby changing its water quality. In this study, the seasonal change and the spatial variation of the water quality in Yongwon channel was analyzed for the effect of land pollution using the measurement data. The mass balance calculation method is used to analyze the water pollution resulting from sediment pollutants. This result shows that the improvement of the water quality in Yongwon channel can be obtained from the sewer pipe modification and the environmental dredging.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.205-214
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• 2007

Surface water and sediment samples collected from the Mokpo coast of Korea were analyzed for molecular markers of organic municipal wastewaters, i.e., 11 fecal sterols including coprostanol (Cop) and nonylphenolic compounds (NPs), to characterize the main routes of these wastewaters to the coast and to assess contamination levels. Concentrations of Cop ranged from 94 to 7,568 ng/L in surface water and from 43 to 38,108 ng/g dry weight in sediments. Concentrations of NPs [nonylphenol (NP) and nonylphenol mono- and di-ethoxylates ($NP_{1-2}EOs$)] ranged from 123 to 4,729 ng/L in surface water and from 4 to 2,119 ng/ng dry weight in sediments. The levels of these compounds were much higher at stations near the rivers that pass through the urban center of Mokpo and the outfall of the wastewater treatment plant (WWTP). The spatial distribution of Cop levels was statistically similar to that of NPs (r=0.809 and 0.982 in surface water and sediments, respectively), indicating that these compounds may have similar discharge points, transport, mixing, and deposition in the study area. These results suggest that considerable amounts of organic wastewater compounds are discharged through rivers and WWTP effluent to the Mokpo coast.