Test of selected bed-material load transport models: Nottawasaga River, Ontario

1994 ◽  
Vol 21 (5) ◽  
pp. 770-777 ◽  
Author(s):  
T. J. Chandler ◽  
R. A. Kostaschuk
Keyword(s):  
Sediment Transport ◽  
Engineering Application ◽  
Model Performance ◽  
Material Transport ◽  
Flow Strength ◽  
Transport Models ◽  
Data Scatter ◽  
Load Transport ◽  
Material Load ◽  
Bed Material

Predictions from 13 bed-material load sediment transport models are compared with 19 measurements of bed-material transport in Nottawasaga River, Ontario, using summary plots and geometric statistics. Model selection is based on recent engineering application and suitability for the flow and sediment conditions of the river. The models of Laursen (1958) and Yang (1979) perform best, followed by those of Ackers and White (1973). The models of Van Rijn (1984), Maddock (1976), Karim and Kennedy (1983), Brownlie (1981), and Yang (1973) have considerable data scatter. The models of Engelund and Hansen (1967) and Shen and Hung (1972) are the poorest predictors. Poor model performance is primarily due to overestimation of flow strength needed for particle entrainment and an excessively steep slope in the relations between flow strength and sediment transport. Key words: bed-material load transport models, test, Nottawasaga River.

scholarly journals Validation of a Novel, Shear Reynolds Number Based Bed Load Transport Calculation Method for Mixed Sediments against Field Measurements

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2051 ◽  
Author(s):  
Gergely T. Török ◽  
János Józsa ◽  
Sándor Baranya
Keyword(s):  
Sediment Transport ◽  
Calculation Method ◽  
Field Measurements ◽  
Sand Transport ◽  
The Novel ◽  
Transport Models ◽  
Meaningful Improvement ◽  
Transport Calculation ◽  
Load Transport ◽  
Bed Material

In this study, the field measurement-based validation of a novel sediment transport calculation method is presented. River sections with complex bed topography and inhomogeneous bed material composition highlight the need for an improved sediment transport calculation method. The complexity of the morphodynamic features (spatially and temporally varied bed material) can result in the simultaneous appearance of the gravel and finer sand dominated sediment transport (e.g., parallel bed armoring and siltation) at different regions within a shorter river reach. For the improvement purpose of sediment transport calculation in such complex river beds, a novel sediment transport method was elaborated. The base concept of it was the combined use of two already existing empirical sediment transport models. The method was already validated against laboratory measurements. The major goal of this study was the verification of the novel method with a real river case study. The combining of the two sediment transport models was based on the implementation of a recently presented classification method of the locally dominant sediment transport nature (gravel or sand transport dominates). The results were compared with measured bed change maps. The verification clearly referred to the meaningful improvement in the sediment transport calculation by the novel manner in the case of spatially varying bed content.

scholarly journals Using high-resolution bedload transport tracer measurements to investigate the characteristics of bedload transport over a large urban flood event

2018 ◽  
Vol 40 ◽  
pp. 04011
Author(s):  
Francesca Berteni ◽  
Benjamin Douglas Plumb ◽  
William Kenneth Annable ◽  
Giovanna Grossi
Keyword(s):  
Sediment Transport ◽  
Low Frequency ◽  
Field Measurements ◽  
Bedload Transport ◽  
Material Transport ◽  
Transport Models ◽  
Material Particle ◽  
Urban Flood ◽  
Bed Material ◽  
Event Based

Channel morphological change is often evaluated by employing sediment transport models since field data during high magnitude low frequency events is rarely available. However, sediment transport rate estimates are heuristic at best to within 1 - 3 orders of magnitude. Mimico Creek is an urban gravel-bed channel in Southern Ontario, Canada that has undergone intensive event-based sediment transport sampling and inter-event bed material particle tracking over a three-year period. A HEC-RAS model was developed of the study reach and calibrated to a series of discharge events where in-situ bedload sampling occurred. Both step-wise discharge and unsteady flow simulations were evaluated to compare sediment transport rates for a range of transport models which included the Meyer-Peter Müller and the Wilcock-Crowe. Calibration curves were developed to estimate sediment discharge in Mimico Creek. The results of the calibrated model were used to calculate the mean travel distance of bed material using the expression for the volumetric rate of bed material transport. Results from the modelling exercise found mean travel distances were similar and in some cases larger than those observed from field measurements, considering both mobile and immobile particles.

scholarly journals Transition from bed-load motion to suspension and its role on bed material load transport.

1990 ◽  
pp. 149-156 ◽  
Author(s):  
Hiroji NAKAGAWA ◽  
Tetsuro TSUJIMOTO ◽  
Shogo MURAKAMI ◽  
Hitoshi GOTOH
Keyword(s):  
Bed Load ◽  
Load Transport ◽  
Material Load ◽  
Bed Material

scholarly journals A Shear Reynolds Number-Based Classification Method of the Nonuniform Bed Load Transport

Water ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 73 ◽  
Author(s):  
Gergely T. Török ◽  
János Józsa ◽  
Sándor Baranya
Keyword(s):  
Reynolds Number ◽  
Sediment Transport ◽  
Comparative Assessment ◽  
Bed Load ◽  
Laboratory Measurements ◽  
Strong Variation ◽  
Load Transport ◽  
Bed Load Transport ◽  
Novel Method ◽  
Bed Material

The aim of this study is to introduce a novel method which can separate sand- or gravel-dominated bed load transport in rivers with mixed-size bed material. When dealing with large rivers with complex hydrodynamics and morphodynamics, the bed load transport modes can indicate strong variation even locally, which requires a suitable approach to estimate the locally unique behavior of the sediment transport. However, the literature offers only few studies regarding this issue, and they are concerned with uniform bed load. In order to partly fill this gap, we suggest here a decision criteria which utilizes the shear Reynolds number. The method was verified with data from field and laboratory measurements, both performed at nonuniform bed material compositions. The comparative assessment of the results show that the shear Reynolds number-based method operates more reliably than the Shields–Parker diagram and it is expected to predict the sand or gravel transport domination with a <5% uncertainty. The results contribute to the improvement of numerical sediment transport modeling as well as to the field implementation of bed load transport measurements.

Sediment transport by tidal currents and implications for slope stability: Fraser River delta, British Columbia

1995 ◽  
Vol 32 (7) ◽  
pp. 852-859 ◽  
Author(s):  
R. A. Kostaschuk ◽  
J. L. Luternauer ◽  
J. V. Barrie ◽  
P. H. Leblond ◽  
L. Werth Von Deichmann
Keyword(s):  
Sediment Transport ◽  
Slope Failure ◽  
Tidal Currents ◽  
River Delta ◽  
Fraser River ◽  
Dune Field ◽  
Fraser River Delta ◽  
Material Load ◽  
And Migration ◽  
Bed Material

Tidal currents on the sandy, southern slope of Fraser River delta have generated dunes with heights of 0.5–3.5 m and lengths of 11–108 m. Dune geometry and migration measurements indicate net sediment transport to the northwest in the direction of flood tidal currents. Two current meters moored in the dune field showed greater frequencies of occurrence and higher mean current speeds in the flood direction compared with the ebb. Predictions from two bed-material load models indicate sediment transport is overwhelmingly dominated by flood currents. There is no obvious source of sand to replace sediment transported in the dune field, suggesting net erosion of the surface. A previous analysis of bathymetric data also shows recent erosion of the lower slope and overall slope steepening. These patterns of erosion could lead to slope failure and damage to coastal structures.

scholarly journals Bed material load estimation in channels using machine learning and meta-heuristic methods

2017 ◽  
Vol 20 (1) ◽  
pp. 100-116 ◽  
Author(s):  
Shahram Sahraei ◽  
Mohammad Reza Alizadeh ◽  
Nasser Talebbeydokhti ◽  
Maryam Dehghani
Keyword(s):  
Machine Learning ◽  
Pso Algorithm ◽  
Least Square ◽  
Support Vector ◽  
Proposed Model ◽  
Load Transport ◽  
Efficient Alternative ◽  
Material Load ◽  
Decision Tree Method ◽  
Bed Material

Abstract This study is trying to develop an alternative approach to the issues of sediment transport simulation. A machine learning method, named least square support vector regression (LSSVR) and a meta-heuristic approach, called particle swarm optimization (PSO) algorithm are used to estimate bed material load transport rate. PSO algorithm is utilized to calibrate the parameters involved in the model to facilitate a desirable simulation by LSSVR. Implementing on a set of laboratory and field data, the model is capable of performing more satisfactorily in comparison to candidate traditional methods. Similarly, the proposed method has a better performance than a specific version of decision tree method. To enhance the model, the variables are scaled in logarithmic form, leading to an improvement in the results. Thus, the proposed model can be an efficient alternative to conventional approaches for the simulation of bed material load transport rates providing comparable accuracy.

scholarly journals The upper Odra as a case study of the impact of channel regulation on its morphodynamics

2014 ◽  
Vol 46 (4) ◽  
pp. 353-361
Author(s):  
Agnieszka Czajka
Keyword(s):  
Sediment Transport ◽  
Material Transport ◽  
Channel Dynamics ◽  
Channel Regulation ◽  
Before And After ◽  
Odra River ◽  
The One ◽  
Bed Material ◽  
The Impact

Abstract The upper Odra as a case study of the impact of channel regulation on its morphodynamics. The aim of the research was to compare morphodynamics of the Odra river channel in three different sectors and to find the main difference in the way of sediment transport before and after regulation in meandering, straight and sinuous channel sectors and compare the data with those calculated for reconstructed, natural channel of the Odra river. Sediment transport in discussed sectors was compared for average, bankfull and flood discharges and it proceeds in different ways. Morphodynamics of the preregulated Odra was most similar to the one currently observed in the meandering section. Also the dynamics of bed-material transport and, consequently, the possibility of the occurrence and disappearance of channel forms is greatly varied among the studied sectors. As it was assumed, a diversified channel geometry imposes water flow, which entails a series of processes shaping the channel dynamics.

scholarly journals A Shear Reynolds Number Based Investigation Method of the Bed Load Transport in Large Rivers with Complex Morphodynamics

2018 ◽  
Author(s):  
Gergely T. Török ◽  
János Józsa ◽  
Sándor Baranya
Keyword(s):  
Reynolds Number ◽  
Sediment Transport ◽  
Measurement Data ◽  
Large Rivers ◽  
Engineering Practice ◽  
Bed Load ◽  
Load Transport ◽  
Bed Load Transport ◽  
Novel Method ◽  
Bed Material

The aim of this study is to introduce a novel method which can separate sand or gravel dominated bed load transport in rivers with mixed-size bed material. In engineering practice, the Shields-Parker diagram could be used for such purposes, however, the method has certain applicability limits, due to the fact that it is based on uniform bed material and provides information rather on river-scale, instead of reach or local scale. When dealing with large rivers with complex hydrodynamics and morphodynamics the bed load transport modes can also indicate strong variation even locally, which requires a more suitable approach to estimate the locally unique behavior of the sediment transport. Here, we suggest that the decision criteria utilizes the shear Reynolds number (Re*). The method was verified against field and laboratory measurement data, both performed at non-uniform bed material compositions. The comparative assessment of the results show that the shear Reynolds number based method operates more reliably than the Shields-Parker diagram and it is expected to predict the sand or gravel transport domination with a &lt; 5% uncertainty. The introduced results can greatly contribute to the improvement of numerical sediment transport modeling as well as to the field implementation of bed load transport measurements.

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