Bedload Transport Velocity: Finding the Signal Amidst the Noise

2002 ◽  
Author(s):  
Colin D. Rennie ◽  
Robert G. Millar
Keyword(s):  
Bedload Transport ◽  
Transport Velocity

Sediment transport over fixed deposited beds in sewers - An appraisal of existing models

1997 ◽  
Vol 36 (8-9) ◽  
pp. 123-128 ◽  
Author(s):  
C. Nalluri ◽  
A. K. El-Zaemey ◽  
H. L. Chan
Keyword(s):  
Sediment Transport ◽  
Fixed Bed ◽  
Transport Equations ◽  
Design Criterion ◽  
Pipe Diameter ◽  
Transport Velocity

An appraisal of the existing sediment transport equations was made using May et al (1989) and Ackers (1991) sediment transport equations for the limit of deposition design criterion and with a deposit depth of 1% of the pipe diameter allowed in the sewers. The applicability of those equations for sewers with larger fixed bed deposit depth was assessed, the equations generally over-estimated the transport velocity. Modifications were made to enable the equations to apply to sewers with large fixed bed deposits present.

An Experimental Study on the Transport of Sediment in Sewer Pipes with a Permanent Deposit

1992 ◽  
Vol 25 (8) ◽  
pp. 115-122 ◽  
Author(s):  
G. S. Perrusquía
Keyword(s):  
Experimental Study ◽  
Critical Shear Stress ◽  
Side Wall ◽  
Bedload Transport ◽  
Flow Conditions ◽  
Sewer Pipes ◽  
Sediment Bed ◽  
Concrete Pipe ◽  
Geometric Factors ◽  
Particle Parameters

An experimental study of the transport of sediment in a part-full pipe was carried out in a concrete pipe. The experiments were confined to bedload transport. The purpose of this study was to analyze the flow conditions that characterize the stream traction in pipe channels and their relationship to flow resistance and sediment transport rate. Three procedures used in this kind of experimental study were tested and found valid: 1) the vertical velocity distribution near the sediment bed can be described by the velocity-defect law, 2) the side wall elimination procedure can be used to compute the hydraulic radius of the sediment bed, and 3) the critical shear stress of the sediment particles can be obtained by using Shields' diagram. A relationship to estimate bedload transport, based on dimensional analysis, was proposed. This was expressed in terms of both flow and particle parameters as well as geometric factors. Further experimental work is recommended before this relationship can be fully incorporated in a simulation model for the analysis of storm sewers.

scholarly journals The intensity of slope and fluvial processes after a catastrophic windthrow event in small catchments in the Tatra Mountains

2021 ◽  
Vol 18 (6) ◽  
pp. 1405-1423
Author(s):  
Dariusz Strzyżowski ◽  
Elżbieta Gorczyca ◽  
Kazimierz Krzemień ◽  
Mirosław Żelazny
Keyword(s):  
Environmental Changes ◽  
Bedload Transport ◽  
Strong Wind ◽  
Tatra Mountains ◽  
Salvage Logging ◽  
Fluvial Processes ◽  
Wind Events ◽  
And Control ◽  
The Tatra Mountains ◽  
The Impact

AbstractStrong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second- to third-order catchments with area ranging from 0.09 km2 to 0.8 km2. Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. We mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. We also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small (total area <100 m2) shallow landslides were created. The mean distance of bedload transport was similar (t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.

Sign in / Sign up

Export Citation Format

Share Document