The Control and Monitoring of Local Scour at Bridge Piers
A series of flume experiments revealed a possible method of reducing local river bed scour at bridge piers, thereby, reducing the risk of bridge failure. Three prototype schemes were installed...
Pressure Relief Under Hydraulic Jump Stilling Basins
Gravity drainage cannot be used for any portion of a structure located below tailwater level. Yet, drainage of this area may be required to relieve sub-floor pressures and reduce the risk...
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...
Storm Drainage Channel Rehabilitation
30 km (19 miles) of existing concrete lines storm drainage channels were studied due to repeated failures. Alternate failures causes were hypothesized and evaluated. Physical testing was...
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...
Threats to Bridge Stability from Scour Related Failures of Drop Structures
Catastrophic failure of bridge foundations may occur when channel bed elevations are lowered unexpectedly. Bridges to be constructed in channels that are known to have bed degradation...
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,...
Model Study of Center Hill Fuse Plug Spillway
Model tests of a fuseplug spillway mounted on the fixed crest of an embankment dam were conducted to develop a satisfactory design that would fail in a orderly fashion at a prescribed...
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...
Time-Dependent Landslide Probability Mapping
Case studies where time of failure is known for rainfall-triggered debris flows can be used to estimate the parameters of a hazard model in which the probability of failure is a function...
Progressive Failure of an Overtopped Embankment
The failure of an overtopped embankment is a problem of a very complicated nature. Concerned organizations are interested in information that can be used in future planning and development...
Local Scour at Bridge Piers in Alberta?Case History
A two span steel truss bridge with a rectangular concrete central pier was built over the Oldman River near Brocket in south-west Alberta in 1954. Initially the bridge was built square...
Probability of Bridge Failure Due to Scouring
Models to estimate depth of scour at bridge piers and abutments are available in many forms,but all of them are based on constant discharges. Their results vary widely and engineering...
Shear Connection in Composite Beams
This paper considers the influence of the shape of the deck profile on the shear connection of composite beams. It was found that the existing strength reduction factor can be unconservative...
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