Journal ArticleDOI
Evaluation and Improvement of Bed Load Discharge Formulas based on Helley–Smith Sampling in an Alpine Gravel Bed River
TLDR
In this paper, bed load discharge formulas have been evaluated by analyzing them in relation to measured Helley-Smith data for the gravel-bedded armored Drau River, Austria, and the choice of formula is made with respect to specific aims: the investigation of individual floods requires a different approach from that of long-term budgets.Abstract:
Bed load discharge formulas have been evaluated by analyzing them in relation to measured Helley-Smith data for the gravel-bedded armored Drau River, Austria. Comparison of calculations with measurements leads to ranking of the formulas that depends on the evaluation parameters. The choice of formula is made with respect to our specific aims: the investigation of individual floods requires a different approach from that of long-term budgets. Formula performance is consistently improved when conditions for the threshold of motion are modified according to data measured up on the initiation of motion. Formulas such as those reported by Parker in 1990, Zanke in 1999, and Sun and Donahue in 2000 are capable of coping with partial transport, which is commonly found in Alpine rivers. These formulas therefore provide encouraging results, particularly after the introduction of modifications. The augmentation of field measurements, even if limited in scope, considerably improves the performance of bed load discharge formulas.read more
Citations
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Journal Article
Closure of "Bedload and Size Distribution in Paved Gravel-Bed Streams"
TL;DR: In this paper, the size distribution of bedload in paved gravel-bed streams was studied and a method for calculating bedload size distribution that accounts for deviation from similarity was developed.
Journal ArticleDOI
A general power equation for predicting bed load transport rates in gravel bed rivers
TL;DR: In this paper, a new bed load transport equation was proposed and identified channel and watershed characteristics that control the exponent and coefficient of the proposed power function, and the exponent is principally a factor of supply-related channel armoring (transport capacity in excess of sediment supply), whereas the coefficient is related to drainage area (a surrogate for absolute sediment supply).
Journal ArticleDOI
Bedform transport rates for the lowermost Mississippi River
TL;DR: In this paper, a multibeam swath profiler was used to collect daily bathymetry over a range of water discharges, and bed elevation changes induced by dune migration are measured.
Journal ArticleDOI
Sediment transport in a large impounded river: The lower Ebro, NE Iberian Peninsula
Damià Vericat,Ramon J. Batalla +1 more
TL;DR: The sediment transport of the highly regulated lower Ebro River is estimated on the basis of a measuring programme carried out between 2002 and 2004 as discussed by the authors, where both suspended load and bedload was measured upstream and downstream from the Mequinenza and Riba-roja reservoirs with special attention to the transport during floods.
Journal ArticleDOI
Testing bedload transport equations with consideration of time scales
TL;DR: In this article, the authors identify how the time scale considered can affect bedload prediction, and test 16 common bedload transport formulas with four data sets corresponding to different measurement period durations: (i) highly fluctuating (quasi-)instantaneous field measurements; (ii) volumes accumulated at the event scale on two small alpine gravel-bed rivers, potentially affected by seasonal fluctuations; (iii) volumes accumulating at the interannual scale in a meandering gravel bed river, thought to be weakly subject to fluctuations.
References
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Formulas for Bed-Load transport
E. Meyer-Peter,R. Müller +1 more
TL;DR: In this article, an attempt is made to derive an empirical law of bed-load transport based on recent experimental data and the results and interpretation of tests already made known in former publications of the Laboratory for Hydraulic Research and Soil Mechanics at the Federal Institute of Technology, Zurich.
The Bed-Load Function for Sediment Transportation in Open Channel Flows
Abstract: CONTENTS Page Introduction. 1 Approach to the problem. _ 3 Limitation of the bed-load function _ _ _ 4 The undetermined function 4 The alluvial stream. 5 The sediment mixture 6 Hydraulics of the alluvial channel. 7 The friction formula 7 The friction factor 8 Resistance of the bars 9 The laminar sublayer 10 The transition between hydraulically rough and smooth beds_ 12 The velocity fluctuations 13 Suspension 14 The transportation rate of suspended load 17 Integration of the suspended load. _ 17 Numerical integration of suspended load 19 Limit of suspension. 24 The bed layer 24 Practical calculation of suspended load___ ____ 25 Numerical example 26 Page Bed-load concept 29 Some constants entering the laws of bed-load motion: 31 The bed-load equation 32 The exchange time 33 The exchange probability 34 Determination of the probability V 35 Transition between bed load and. suspended load 38 The necessary graphs 40 Flume tests with sediment mixtures.. 42 Sample calculation of a river reachl 44 Choice of a river reach 45 Description of a river reach_____ 45 Application of procedure to Big Sand Creek, Miss 46 Discussion of calculations 60 Limitations of the method____ 65 Summary. 67 Literature cited 68 Appendix 69 List of symbols. 69 Work charts _ 71
Journal ArticleDOI
Sediment Transport: New Approach and Analysis
TL;DR: In this article, the relationship of sediment transport to fluid flow is considered and predictive equations are derived which relate total sediment flux to measurable properties of flow, and a preliminary comparison is made with observations from other sources, including natural rivers.
Journal ArticleDOI
Settling velocity of natural particles
TL;DR: In this paper, the effects of size, density, shape, and roundness on the settling velocity of natural sediment were analyzed in terms of four non-dimensional parameters, namely, the dimensionless nominal diameter D*, W*, the Corey shape factor, and the Powers roundness index.