• Advances in concrete construction
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• v.4 no.1
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• pp.15-26
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• 2016

In Algeria, wastes are often stored in such conditions that do not meet standards. Today and more than ever, we really must implement an environmentally management of wastes. Recovery of waste in Algeria has a considerable delay due to the absence of a policy favorable to the development of waste management. But many researchers have shown the possibility to reuse dredged sediments in road construction. Through Europe, recent research works have been already performed on dam sediments. Present study fits into the context of the valorization of dredged sediments from Fergoug dam. They are found in considerable quantities and mainly composed of mineral phases, organic matters and water. The reservoir sedimentation poses problems for the environment and water storage, dredging becomes necessary. Civil engineering is a common way of recycling for such materials. Dredged sediments have not the required mechanical characteristics recommended by the standards as GTR guide (LCPC-SETRA 1992). So as to obtain mechanical performance, dredged sediment can be treated with cement, lime, or replaced materials like quarry sand. An experimental study has been conducted to determine physical and mechanical characteristics of sediments dredged from dam. Then different mixtures of sediment and/or quarry sand with hydraulic binders are proposed for improving the grain size distribution of the mixes. Finally, according these mixtures, different formulations have been tested as alternative materials with dredged sediments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.286-294
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• 2008

In order to understand the physical properties of deep-sea sediments, which mainly consist of pelagic red clays, sediment samples were collected at 24 stations using a multiple corer in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific. The sampled sediment cores were examined for the mass physical properties(i.e. grain size distribution, mean grain size, water content, specific grain density, wet bulk density, void ratio, and porosity) and the geotechnical properties(i.e. shear strength and consistency limits) with the content of biogenic opal and mineral composition. Although KR1 and KR2 areas on the same latitude are logitudinally far from each other, the mass physical properties of these areas are not distinctly different except for shear strengths. The maximum shear strength of surface sediments in KR2 area is higher than that in KR1 due to the appearance of a consolidated lower layer(Unit 3) in the sediment core from KR2.

• The Journal of the Acoustical Society of Korea
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• v.23 no.5
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• pp.362-369
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• 2004

The High-frequency (30 ∼ 120 ㎑) bottom reflection loss at rough water-sediment interface is affected by the gram size distribution of the sediments. The roughness of the bottom surface is represented by "acoustical roughness. g/sub R/" The grain size of sandy sediments is g/sub R/∼O(1) and the dependence as a function of frequency. We suggest the modified bottom reflection loss model (HYBRL model , HanYang university Bottom Reflection Loss model) that include in the deviation of the reflection loss as a function of the grain size distribution and frequency dependence. And bottom reflection loss model of frequency dependence and deviation of bottom properties is verified by water tank and field experiments.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.1-17
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• 2018

The characteristics and burial ages of sand sediments on the Jiduri coast in Daechung-myeon, Ongjin-gun, Incheon were investigated. Daecheong Island is the area where the characteristics of the rocky coast and sand coast are shown. Various studies have been conducted on the Okjukdong sand dune that appears in the north of the island. However, there has been no study on the sandy sedimentary topography of the Jiduri and Moraewul area in the south. The sandy sedimentary terrain of Jiduri is divided into sandy beaches, sand dunes and sand deposits along the slope including climbing dune. Overall, the depth of sandy sediments in Jiduri is not deep. The characteristics of sandy sediments and burial ages were investigated at an elevation of about 23 m above sea level at the back of Jiduli Beach and 46 m above sea level at the ridge line between Jiduri and Moraewol. From the Jiduri coast to the hillside behind, the average grain size decreases and the sorting becomes better as it moves from the intertidal zone to the beach and the foredune. This indicates the selective sand transport by the wind and can be judged by the terrain formed under the current sedimentation environment. The average grain size at the upper part of the section of JD-1 (elevation of about 23m MSL) was $1.6918{\varphi}$ of medium sand. The sorting was $0.4584{\varphi}$, skewness was -1.0491 and kurtosis was -1.2411, respectively. Particularly, the average particle size of the crosssection issomewhat uniform, but the color of the constituent material changes from brown to black. In the case of JD-2 (about 46 m MSL), the mean grain size of the section was $1.7943{\varphi}$, the sorting was 0.4931, the skewness was -1.1163, and the kurtosis was 1.2133. On the other hand, the brown and black layers of JD-1 exhibited a burial age of $0.1{\pm}0.0ka$ and the JD-2 had a burial age of $0.7{\pm}0.0ka$.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.281-288
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• 2013

In this study we estimated the carrying capacity of the southern intertidal zone of Kanghwa Island to evaluate the habitat quality for Curlews(Far Eastern Curlew Numenius madagascariensis and Eurasian Curlew Numenius arquata). Biomass of the macroinvertebrate(Macrophthalmus japonicus) was estimated by based on the spatial distribution of the sediment grain size using GIS tools. According to our analysis the southern intertidal zone of Kanghwa Island was able to support 11,767 individuals for 153 days in the Spring 2012 and 16,275 individuals for 122 days in the Autumn 2012. The proportion of mean population to the carrying capacity in the Spring and Autumn was 9.4% and 5.9%, respectively. These values are 2.8-6.3% smaller than those of the previous study held in 1993-94. For the conservation of the study area, more research and management is needed. And in further studies, diverse characteristics of the intertidal habitat should be considered in spatial analysis to have a precise estimate of the carrying capacity.

• The Journal of Engineering Geology
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• v.25 no.2
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• pp.273-280
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• 2015

Delays in horizontal well drilling when encountering heterogeneous sediments can have negative effects on the construction process at a riverbank filtration site. Grain size analysis, including calculation of the coefficient of uniformity and the coefficient of curvature, was conducted on soil samples collected at each drilling depth during the process of drilling horizontal wells. These results were then used to develop a linear equation for estimating drilling velocity using the coefficient of uniformity and the coefficient of curvature as inputs. Testing of the linear equation in other horizontal wells indicates that the equation is most appropriate for coarse-sand-sized and well-sorted sediment. Because this study was conducted in a region with small- to medium-sized streams, more data are needed from larger rivers to modify the general equation. Our results will provide better estimates of drilling velocity, in turn enabling more detailed design and more effective construction management at riverbank filtration sites.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.520-527
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• 2005

In order to investigate the geochemical characteristics of surface sediments in streams of upper Yeongsan River drainage system, sediment samples from the main stream of Yeongsan river, Hwangryong river, Gwangju and Jiseok streams were collected and analyzed for grain size and metal and organic carbon contents. The metal contents in the sediments are mainly dependent on organic matter contents in the domestic sewage, grain size of the sediments and geology around the streams. Enrichment factor (EF) and index of geoaccumulation (Igeo) representing the degree of metal contamination in the sediments are relatively low in the main stream of Yeongsan river main stream, Hwangryong river and Jiseok stream. However, those of Gwangju stream show the EF maximum values of P=8.30, Cu=5.55, Zn=14.29 and Pb=7.45 and the Igeo maximum values of P=3.58, Cu=4.43, Zn=3.22 and Pb=1.59.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.246-253
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• 1999

Grain size distributions of sediment samples were analyzed by the different methods, and the results were compared. Reported data of the bottom sediments from the Korean seas show significant deviations among the institutes, and the inter-lab comparison and calibration procedures are considered to be necessary. Grain size data by different methods show different results. Laser diffraction method provides good precision in replicate analysis, but underestimates the amounts of finer (smaller than 2-3 ${\mu}m$) fraction. Data from particle settling method, on the other hand, represent significant errors in the coarse silt (5-6 ${\phi}$) fraction, and slightly overestimate the clay fraction. In the sieve and pipette methods, best results were taken in 0.5 ${\phi}$ interval of analysis. Especially in the coarse silt fraction, pipette analysis is suggested to be made with 0.5 ${\phi}$ interval. During the dry sieving procedure in 1 ${\phi}$ interval, serious errors occur when large amounts of sample materials were concentrated in a particular sieve.

• Korean Journal of Ecology and Environment
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• v.48 no.3
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• pp.168-175
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• 2015

This study was conducted in autumn to determine phosphorus (P) fraction in sediments of Daechung Lake, to elucidate controlling factors for sedimentary P, and to compare with the other areas. For this study, sediment samples were collected at 6 sites only once on November 2014 using ponar grab and analyzed for solid-phase P (Loosely adsorbed, Fe-bound, Al-bound, detrital apatite, and refractory organic P) by sequential extraction. Total phosphorus (TP) was relatively high in front of Daechung Dam and Hoinam where fish farm was run until 1997. The dominant sedimentary P form was Al-bound P, followed by Fe-bound P, which could be released from sediment to water column during suboxic state. Based on principal component analysis, Al-bound P, Fe-bound, and TP were controlled by grain size of sediments. Loosely adsorbed, detrital apatite, and refractory organic P were relatively highly accumulated at the mouth of major tributaries where suspended sediments were delivered. Sedimentary P concentrations in Daechung Lake sediments were not higher than in other lake sediments. Therefore, based on these results, major controlling factors were grain size and input of suspended sediments from tributaries.

• Journal of The Geomorphological Association of Korea
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• v.21 no.4
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• pp.109-120
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• 2014

This study is an analysis on gravel and sand of sand-gravel bar that stretches variously in the Duchon stream basin, which is one of Hong-Cheon River(a well-developed sand-gravel bar in upstream river)'s upper stream basin. The purpose of this study was to understand the characteristic of the stream's topographic development that variously occur in the small basin by comparing the differences between the aspects of development and the sediment of sand-gravel bar in each section and by examining the transition of sediments moving from upstream to downstream. Through the analysis on the roundness and flatness of gravel, we observed an irregular trend following the increase in supply of granite gravel and gneiss gravel as we traveled downstream. As for the aspect of change in sand's grain size, the overall ratio of medium-coarse sand was very high, but the results showed no big difference in the change following the inflow of stream from the main stream section to the gneiss and granite zone.