Incipient Motion in Gravel-Bed Rivers
Incipient motion processes are reviewed for bed material in gravel-bed rivers. Prediction difficulties are identified. Research results are reported for field and flume studies to investigate...
Sediment Budgets in Gravel Bed Streams
A sediment budget/mass balance technique is presented for use in assessment of sediment transport by river reach in gravel bed streams. Selection of appropriate gravel bed transport equations,...
Plunge-Pool Aeration Due to Inclined Jets
The present study quantifies how jet height and nozzle inclination angle and diameter affect the rate of air entrained by inclined circular jets. An air-collection hood and a vacuum pump...
Bed Sediments Size Changes, Atchafalaya River
During low flows of 1989 and 1991, we collected bed sediment samples from the thalwegs of the Mississippi River from Cairo, Illinois, to Head of Passes and along the Atchafalaya River...
A Study of Lateral Bed Slopes Developed at Bend
A study was conducted to compare seven actual cross section profiles of Philip Bayou Realignment with the lateral bed slopes estimated from the model derived by Ikeda titled `Sediment...
Effect of Grain Size on Sediment Transport Calculations
The U.S. Army Corps of Engineers is currently developing a `Hydraulic Design Package for Flood Control Channels' (SAM). SAM is capable of computing sediment rating curves and stable channel...
Top Width of Pier Scour Holes in Free and Pressure Flow
The maximum top width of the local scour holes at piers is shown to be a simple function of the scour depth and the angle of repose of the bed material in water. Knowledge of the top width...
Video Analysis of Gravel Saltation
Experimental results concerning saltation characteristics of gravel particles in a movable bed channel are analyzed by using video imaging techniques. Ensemble averaged values of saltation...
n Values for Shallow Flow in Rough Channels
Manning's friction factor n has been developed from flume data for very shallow open channel flow in a high-gradient channel with large bed material. n values are presented as a function...
Comparison of Theoretical and Historical Scour
As part of scour assessments at approximately 120 stream crossings on the New York State Thruway, subsurface investigations were performed at all structures and, in some instances, locations...
Sediment Disposal and Transport in Central SF Bay
The relocation of dredged material from navigation channels in the Francisco Bay is crucial to the movement of deep-draft shipping and shallow-draft recreational vessels. The margins of...
Survival of Atlantic Salmon Smolts Bypassed Through Ice-Log Sluices Determined by the HI-Z Turb'N Tag
The HI-Z Turb'N Tag was used to assess injury and mortality incurred by Atlantic Salmon (Salmo salar) smolts bypassed through ice-log sluiceways at two stations. Both sluiceways were similar...
The Influence of Protective Material on Local Scour Dimensions
Protective materials installed around the base of a bridge pier can reduce or prevent local scour. The performance of four materials: grout mats, grout bags, footings, and riprap, are...
Tetrapods as a Scour Countermeasure
Few materials have been studied for their effectiveness in protecting bridge piers and abutments from local scour other than riprap. Recent research conducted at the FHWA research facility...
Mechanics of Debris Flows
The paper deals with the mechanics aspects of the modelling of debris flows and will focus on steady, fully developed flows. After a brief review of the types of constitutive equations...
Kenetic-theory Approach to the Nevado Del Ruiz 1985 Debris Flow
The Nevado del Ruiz 1985 debris flow was the worst disaster of its kind in this century, killing 22,000 people. By making an idealization of the debris flow material and the flow regime,...
An Application of Nonhomogeneous Poisson Process in Sediment Infiltration Into Gravel Bed
The compound homogenous Poisson process (CNHPP) model (Shen & Todorovic, 1971 ) is found applicable in sediment infiltration into gravel bed due to the unsteady and nonuniform...
Riprap Coverage Around Bridge Piers
Experiments were conducted to examine the effect of riprap size and coverage on reducing local scour at bridge piers. Pier diameter, bed material size, riprap size and diameter were varied...
Friction in Debris Flows: Inferences from Large-scale Flume Experiments
A recently constructed flume, 95 m long and 2 m wide, permits systematic experimentation with unsteady, nonuniform flows of poorly sorted geological debris. Preliminary experiments with...
Sediment Deposition from Debris Flow on a Gentle and Wide Slope
Motion of sediment grains in the deposition process from debris flow on a gentle and wide slope was examined. A model of the deposition was presented on the basis of an analysis of grain...
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