A Tidal Inlet Bridge Scour Assessment Model
Undermining of bridge structures constructed in tidal inlets is a common problem. Scour mechanisms in tidal inlets are often complex combinations of local contraction and regional tidal...
Fish Screen Developments, Columbia River Dams
This paper describes developments to date for a fish diversion and bypass system being tested for two Columbia River dams. Because of the concern for the negative impacts of screen systems...
Flow Resistance Properties of Flexible Linings
Flow resistance for flexible channel linings is a function of the relative roughness of the lining in accordance with boundary-layer principles. As with vegetation, flexible linings have...
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...
Rheometry of Natural Sediment Slurries
Recent experimental analyses of natural sediment slurries yield diverse results yet exhibit broad commonality of rheological responses under a range of conditions and shear rates. Results...
Repeatability and Oblique Flow Response Characteristics of Current Meters
Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement...
Bed Shear Stress in Unsteady Open-Channel Flows
In this study, velocity distributions over smooth and rough beds were accurately measured with an LDA in unsteady open-channel flows. The log-law distributions yielded well in the wall...
Riprap Design at Bridges?Factor of Safety Approach
The factor of safety method offers a physically based methodology for design of riprap that relates the applied shear stress on the channel boundary to the stability of the riprap layer....
Riprap Incipient Motion and Shields' Parameter
Unobstructed incipient motion data from a variety of sources are compiled to re-examine current thinking regarding riprap stability. Shields' framework is investigated and relationships...
Laboratory Study of the Characteristics of Shallow Open Channel Flow Using Fiber-optic Laser Doppler Velocimetry
An experimental study was proposed to investigate the characteristics of shallow rain-impacted flow using a recirculating flume and an artificial rainfall simulator. The fibre-optic Laser...
Turbulent Velocity Flutuations in Natural Rivers
The longitudinal and transverse components of flow velocity, as well as the normal and tangential stresses, must be expected to fluctuate with time and space when flow at a high Reynolds...
Hydraulic Model Studies of Y-Branch
Hydraulic model studies were made for the Y-branch steel penstock located in a vertical bend. The model tests were performed for various modes of pumping and generating operation. The...
Confirmation of Seismic Safety at Stafford Dam
A critical aspect of the North Marin Water District's mission to maintain reliable water supply facilities and water service is periodic assessment and re-evaluation of the seismic safety...
Pier Scour on the South Saskatchewan River
A continuing program to measure river bed scour near bridge piers and abutments on the Alberta rivers has been on going for over thirty years. The objectives are to verify the existing...
Bridge Scour Prediction Methods Applicable to Streams in Pennsylvania
The Pennsylvania Department of Transportation, PennDOT, currently owns or maintains in excess of 28,000 bridges over 8 feet in length. The most common type of damage sustained by these...
Scour Inspection Using Ground Penetrating Radar
This paper examines the capabilities of Ground Penetrating Radar (GPR) for river bed scour inspection based on a study carried out by Clarkson University, Potsdam, New York in association...
Large-Scale Embankment Overtopping Protection Tests
The U.S. Bureau of Reclamation (Reclamation), Colorado State University (CSU), and the Electric Power Research Institute (EPRI) have an ongoing cooperative research effort to determine...
Ballast Water Treatment Effluent Dispersion Studies
Treated tanker ballast water is discharged form Alyeska Pipeline Service Company's ballast water treatment facility through a multiport diffuser into Port Valdez, Alaska. The discharge...
Evaluation of an Existing Scour Hole at the Castleton Bridge, a Tidal Crossing
Several fathometric surveys conducted in recent years showed a large depression or scour hole on the downstream southeast corner of the central pier of the Castleton Bridge over the Hudson...
Using Geophysical Data to Assess Scour Development
The development of scour holes in the Connecticut River near the new Baldwin Bridge has been documented by comparing geophysical records collected before (1989), during (1990), and after...
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