scholarly journals Comparison between Calculation and Measurement of Total Sediment Load: Application to Nestos River

2020 ◽  
Vol 2 (1) ◽  
pp. 19
Author(s):  
Loukas Avgeris ◽  
Konstantinos Kaffas ◽  
Vlassios Hrissanthou
Keyword(s):  
Suspended Sediment Concentration ◽  
Sediment Load ◽  
Sediment Concentration ◽  
Stream Discharge ◽  
Nestos River ◽  
Engineering Department ◽  
Load Transport ◽  
Bed Load Transport ◽  
Total Sediment ◽  
Statistical Criteria

Measurements of stream discharge, bed load transport rate and suspended sediment concentration in the Nestos River (northeastern Greece) were conducted by the Section of Hydraulic Engineering, of the Civil Engineering Department, Democritus University of Thrace. In addition to those measurements, the total sediment concentration was calculated by means of the formulas of Yang. The comparison between the calculated and measured total sediment concentration was achieved by means of several statistical criteria and the results were deemed satisfactory.

scholarly journals Regression analysis between sediment transport rates and stream discharge for the Nestos River, Greece

2013 ◽  
Vol 14 (3) ◽  
pp. 362-370
Keyword(s):  
Sediment Transport ◽  
Suspended Load ◽  
Bed Load ◽  
Regression Curve ◽  
Degree Polynomial ◽  
Stream Discharge ◽  
Nestos River ◽  
Polynomial Curve ◽  
Load Transport ◽  
Bed Load Transport

Systematic measurements of sediment transport rates and water discharge were conducted in the Nestos River (Greece), at a place located between the outlet of Nestos River basin and the river delta. This basin area is about 838 km2 and lies downstream of the Platanovrysi Dam. Separate measurements of bed load transport and suspended load transport were performed at certain cross sections of the Nestos River. In this study, relationships between sediment transport rates and stream discharge for the Nestos River are presented. A nonlinear regression curve (4th degree polynomial curve; r2 equals 0.62) between bed load transport rates and stream discharge, on the basis of 63 measurements, was developed. In addition, a nonlinear regression curve (5th degree polynomial curve; r2 equals 0.95) between suspended load transport rates and stream discharge, on the basis of 65 measurements, was developed. The relatively high r2 values indicate that both bed load transport rates and, especially, suspended load transport rates can be predicted as a function of the stream discharge in the Nestos River. However, the reliability of the regression equations would have been higher if more measured data were available.

scholarly journals Sediment Transport During an Outburst from Glacier De Tsidjiore Nouve, Switzerland, 16–19 June 1981

1983 ◽  
Vol 29 (101) ◽  
pp. 185-190 ◽  
Author(s):  
Ian Beecroft
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Suspended Sediment Concentration ◽  
Sediment Concentration ◽  
Bed Load ◽  
Stream Discharge ◽  
Large Water

AbstractBetween 16 and 19 June 1981 a large water pocket of volume 183 000 m3 burst from glacier de Tsidjiore Nouve. From hourly stream discharge and suspended sediment concentration observations a suspended sediment output of 1 674 × 103 kg was calculated. The transport of bed-load was estimated at 3 840 × 103 kg, hence a total quantity of around 5 500 × 103 kg of sediment were removed from the catchment, including the pro-glacial field, in the four days of the outburst.

scholarly journals Sediment Load and Suspended Sediment Concentration Prediction

2013 ◽  
Vol 1 (No. 1) ◽  
pp. 23-31 ◽  
Author(s):  
Bečvář Martin
Keyword(s):  
Suspended Sediment ◽  
Sediment Yield ◽  
Suspended Sediment Concentration ◽  
Sediment Load ◽  
Sediment Concentration ◽  
River Basins ◽  
River Systems ◽  
Sediment Yields ◽  
Suspended Sediment Concentrations ◽  
Annual Sediment

Sediment is a natural component of riverine environments and its presence in river systems is essential. However, in many ways and many places river systems and the landscape have been strongly affected by human activities which have destroyed naturally balanced sediment supply and sediment transport within catchments. As a consequence a number of severe environmental problems and failures have been identified, in particular the link between sediments and chemicals is crucial and has become a subject of major scientific interest. Sediment load and sediment concentration are therefore highly important variables that may play a key role in environment quality assessment and help to evaluate the extent of potential adverse impacts. This paper introduces a methodology to predict sediment loads and suspended sediment concentrations (SSC) in large European river basins. The methodology was developed within an MSc research study that was conducted in order to improve sediment modelling in the GREAT-ER point source pollution river modelling package. Currently GREAT-ER uses suspended sediment concentration of 15 mg/l for all rivers in Europe which is an obvious oversimplification. The basic principle of the methodology to predict sediment concentration is to estimate annual sediment load at the point of interest and the amount of water that transports it. The amount of transported material is then redistributed in that corresponding water volume (using the flow characteristic) which determines sediment concentrations. Across the continent, 44 river basins belonging to major European rivers were investigated. Suspended sediment concentration data were collected from various European basins in order to obtain observed sediment yields. These were then compared against the traditional empiric sediment yield estimators. Three good approaches for sediment yield prediction were introduced based on the comparison. The three approaches were applied to predict annual sediment yields which were consequently translated into suspended sediment concentrations. SSC were predicted at 47 locations widely distributed around Europe. The verification of the methodology was carried out using data from the Czech Republic. Observed SSC were compared against the predicted ones which validated the methodology for SSC prediction.

scholarly journals Comparison between Computations and Measurements of Bed Load Transport Rate in Nestos River, Greece

2016 ◽  
Vol 162 ◽  
pp. 172-180 ◽  
Author(s):  
Thomas Papalaskaris ◽  
Paraskevi Dimitriadou ◽  
Vlassios Hrissanthou
Keyword(s):  
Transport Rate ◽  
Bed Load ◽  
Nestos River ◽  
Load Transport ◽  
Bed Load Transport

scholarly journals SEDIMENT TRANSPORT UNDER SHEET FLOW CONDITION

1982 ◽  
Vol 1 (18) ◽  
pp. 82 ◽  
Author(s):  
Kiyoshi Horikawa ◽  
Akira Watanabe ◽  
Sadakazu Katori
Keyword(s):  
Sediment Transport ◽  
Flow Condition ◽  
Average Rate ◽  
Empirical Relationship ◽  
Sediment Concentration ◽  
Transport Rate ◽  
Sheet Flow ◽  
Load Transport ◽  
Bed Load Transport ◽  
Moving Layer

A series of laboratory experiments in an oscillatory tank was carried out to investigate the sheet flow of sediment. Objectives of the study were to determine the criterion for inception of sheet flow, and to evaluate the sediment transport rate under the sheet flow condition. In order to proceed with the investigation, it was necessary to develop devices appropriate for tracing the sediment particle movement, and for measuring the extremely dense sediment concentration in the moving layer of sheet flow. The chief results are: 1) the criteria for the inception of sheet flow given by Manohar C1955) and by Komar and Miller (1974) are both applicable to materials composed of spheroidal particles, and 2) the average rate of sediment transport for sheet flow is well described by an empirical relationship given by Madsen and Grant (1976) for the bed load transport rate on a plane bed in oscillatory flow.

Dynamics of Suspended Sediments Related to Fine Particles in Lower Mekong River

2013 ◽  
Vol 446-447 ◽  
pp. 1528-1533
Author(s):  
Sarunya Promkotra
Keyword(s):  
Shear Stress ◽  
Flow Velocity ◽  
Suspended Sediment ◽  
Suspended Sediment Concentration ◽  
Fine Particles ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Mekong River ◽  
Fall Velocity ◽  
Stream Discharge

Analytical results are considered the factors of suspended sediment concentration, fall velocity, dimensionless shear stress, transportation rate and stream discharge. As a result of suspended sediments of Loei, Huang and Mekong River, fine particles account for the applicability in sediment deposits. Floating suspended sediments explicit more clay minerals than suspended sediments. Suspended sediment concentration (SSC) in the estuarine of Loei River and Huang River are moderately less than Mekong River. Flow directions of the interconnected rivers to the mainstream-Mekong River lead to the quantity of SSC. Sediment concentrations attain to the dynamic response. Dimensionless shear stress relates to shear velocity, geometry and grain size of particles, and difference of flow velocity. This shear stress is directly comparative to flow velocity and clay mineral concentrations. The transport rate involves in the flow velocity, SSC and depth of the river. Moreover, stream discharge can be presumed by the geometry of the river and topography of sampling locations.

scholarly journals Parameter Optimization of a Bed Load Transport Formula for Nestos River, Greece

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 627 ◽  
Author(s):  
Epameinondas Sidiropoulos ◽  
Thomas Papalaskaris ◽  
Vlassios Hrissanthou
Keyword(s):  
Nonlinear Optimization ◽  
Parameter Optimization ◽  
Roughness Coefficient ◽  
Bed Load ◽  
International Conference ◽  
Average Value ◽  
Nestos River ◽  
Load Transport ◽  
Bed Load Transport ◽  
Bed Roughness

In the Second EWaS International Conference (June 2016, Chania, Crete, Greece), the bed load transport formula of Meyer-Peter and Müller (1948) was calibrated with respect to the bed roughness coefficient for Nestos River. The calibration was manual and incremental, taking five measured values of bed load transport rate at a time. In contrast, the present study carries out a nonlinear optimization of two suitable parameters, while utilizing the average value of the roughness coefficient kst found by the manual calibration. Thus, a uniform calibration is attained, by taking at once the totality of the available 68 measurement points. The results did not show any marked fitting improvement in comparison to the previous study. However, considering moving averages of the measured bed load transport values yields a better adjustment of the model to the measured results.

scholarly journals Decline of Fine Suspended Sediments in the Madeira River Basin (2003–2017)

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 514 ◽  
Author(s):  
Irma Ayes Rivera ◽  
Elisa Armijos Cardenas ◽  
Raúl Espinoza-Villar ◽  
Jhan Espinoza ◽  
Jorge Molina-Carpio ◽  
...  
Keyword(s):  
Suspended Sediment Concentration ◽  
Sediment Load ◽  
Water Discharge ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Hydropower Potential ◽  
Madeira River ◽  
Fine Suspended Sediment ◽  
Porto Velho ◽  
Madeira River Basin

The Madeira River is the second largest Amazon tributary, contributing up to 50% of the Amazon River’s sediment load. The Madeira has significant hydropower potential, which has started to be used by the Madeira Hydroelectric Complex (MHC), with two large dams along the middle stretch of the river. In this study, fine suspended sediment concentration (FSC) data were assessed downstream of the MHC at the Porto Velho gauging station and at the outlet of each tributary (Beni and Mamoré Rivers, upstream from the MHC), from 2003 to 2017. When comparing the pre-MHC (2003–2008) and post-MHC (2015–2017) periods, a 36% decrease in FSC was observed in the Beni River during the peak months of sediment load (December–March). At Porto Velho, a reduction of 30% was found, which responds to the Upper Madeira Basin and hydroelectric regulation. Concerning water discharge, no significant change occurred, indicating that a lower peak FSC cannot be explained by changes in the peak discharge months. However, lower FSCs are associated with a downward break in the overall time series registered at the outlet of the major sediment supplier—the Beni River—during 2010.

Experimental Study of Sand Sediments Effects on Submerged Hydraulic Jump Properties

2012 ◽  
Vol 212-213 ◽  
pp. 366-371
Author(s):  
Siavash Haghighi ◽  
Mohammad Reza Kavianpour ◽  
Keyvan Nasiri
Keyword(s):  
Energy Dissipation ◽  
Hydraulic Jump ◽  
Suspended Sediment Concentration ◽  
Sediment Load ◽  
Sediment Concentration ◽  
Relative Energy ◽  
Sluice Gate ◽  
Jump Length ◽  
Submerged Hydraulic Jump ◽  
Whole Sediments

Abstract. In this study, the effect of sediment concentration on submerged hydraulic jump (SHJ) characteristics such as jump length, submerged depth on the gate and the energy dissipation is investigated. Experiments were carried out in a flume of 46 cm depth, 12 m length. The width of the flume changes from 10 cm (at the entrance) to 60 cm (at the exit). Sediment load and flow concentration have an influence on submerged hydraulic jump characteristics including submerged depth on the gate, jump length and relative energy dissipation. It is shown that at high Froude numbers increasing the suspended sediment concentration to 28.7 gr/l leads to a reduction in the submerged depth on the gate up to 6% and jump length up to 10%. Also, the energy dissipation of the submerged hydraulic jump increases by 4% and turbulence resulting from the jump leads to upright distribution of concentration at the end of the jump. Also in concentrations higher than 30 gr/l, flow is not able to carry the whole sediments and subsequently leads to their deposition in subcritical area and behind the sluice gate.

scholarly journals Dynamics of suspended sediment load in the Morava River (Serbia) in the period 1967-2007

2016 ◽  
Vol 18 (1) ◽  
pp. 47-58
Author(s):  
Sanja MANOJLOVIĆ ◽  
Predrag MANOJLOVIĆ ◽  
Mrdjan DJOKIĆ
Keyword(s):  
Suspended Sediment ◽  
Suspended Sediment Concentration ◽  
Sediment Load ◽  
Water Discharge ◽  
Sediment Concentration ◽  
Suspended Sediment Load ◽  
Test Results ◽  
Pettitt Test ◽  
Mk Test ◽  
Morava River

The study is concerned with determination of the trend of water discharge, suspended sediment concentration and sediment load in the most downstream profile of the Velika Morava River in the period 1967-2007. The gradual trend test (Mann–Kendall test – MK test) and abrupt change test (Pettitt test) have been employed on annual, seasonal and monthly water discharge, suspended sediment concentration and suspended sediment load for the given time series. Both the Mann–Kendall and Pettitt tests indicate that water discharge showed no significant annual trend or abrupt shift. However, annual suspended sediment concentration and sediment load showed significant decreasing trends (α=0.001). The average decrease of suspended sediment load transport amounted to 3.15 t/km2/yr. The Pettitt test results showed that the change-point year was detected in 1982. The average specific sediment load amounted to 134.6 t/km2/yr before the transition year, and 36.5 t/km2/yr after the transition year, i.e., it was reduced by 73 %. In the intra-annual distribution, the MK test results indicate that the most pronounced decreasing trend (α=0.001) of the sediment load is during summer and winter. Strong seasonal and monthly variability in sediment load was found. Sediment was strongly transported during spring months, in the period of frequent flood events. Almost 50% of the annual sediment is transported during March, April and May. Analysis of the discharge and suspended sediment concentration relationship revealed the existence of hysteresis loop in the shape of figure eight. The results of this study confirm the complex and heterogeneous nature of sediment response in the Velika Morava River.

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