Pier Scour at Wide Piers
Scour at relatively wide piers in shallow water is not explicitly accounted for in the current HEC-18 scour equation. The scour estimated for this case is often overpredicted. In this...

Impacts of NAFTA on Environmental Engineering
This paper addresses recent developments in the environmental sector under the North American Free Trade Agreement (NAFTA). The North American Free Trade Agreement (NAFTA) represents a...

Sanata Ana River Project Environmental Compliance with the National Environmental Policy Act (NEPA)
The National Environmental Policy Act(NEPA) was first enacted in. 1969, and became effective as of January 1, 1970. The law was intended to ensure that balanced decision-making occurs...

Scour Around Circular Piers
In certain situations scour classification becomes sensitive. The generalised scour relationships are superior to classification dependent scour relationships. In this study a generalised...

Temporal Development of Local Scour at Bridge Piers
The temporal development of local scour depth at circular cylindrical bridge piers is considered. New data are presented and used to quantify the influence of flow duration on the depth...

Maryland SHA's Procedure for Assessing Existing Bridges for Scour Vulnerability and for Rating Unknown Foundations
The Maryland State Highway Administration developed a recommended screening procedure for rating existing bridges for Item 113, Scour Critical Bridges, in the National Bridge Inventory...

Measurements of Bridge-Scour Depths in Mississippi
This paper briefly summarizes 190 measured pier-scour depths collected dur ing 1942?94 at 22 selected bridges in Mississippi and presents an envelope-curve equation for the data. The envelope-curve...

Field Measurements of Streambed Scour at Bridge Piers in Ohio
Field measurements made from 1989 to 1994 were evaluated to characterize pier scour at 21 bridge sites in Ohio. Pier scour was observed at sites in 45 of 47 real-time scour measurements....

Scour-Hole Dimensions at Selected Bridge Piers in New York
Knowledge of scour-hole dimensions can be used by bridge engineers to deter mine the extent of countermeasures needed to prevent scour at bridge piers. Scour-hole widths at 128 piers,...

Scour Processes Observed in Field Data
River channels scour and aggrade due to complex, interrelated natural processes that are dynamic over space and time. Channel scour is particularly difficult to predict for bridge crossings,...

Channel Scour Protection at Roadway Crossings
There are several forms of channel scour which may damage a bridge or culvert crossing over a natural or improved channel. Typical forms of scour include general degradation, local scour...

Assessment and Implications of Local Channel Instability on the Prediction of Bridge Scour
Current assessments of the potential for scour at existing and new bridges do not include the effects of local channel instability on predicted bridge scour estimates. Local channel instability...

Use of Geomorphic Data for Assessing Stream Stability at Bridge Structures
The authors recently completed a statewide bridge scour evaluation for the Nevada Department of Transportation, which included evaluation of the geomorphic processes of bank erosion and...

The Cost of Highway Bridge Scour in the State of Minnesota
Different states are faced with different conditions with respect to geology, topography, climate, native vegetation types, bridge ownership, and bridges management systems, which in turn...

Contraction Scour at Bridges: Analytic Model for Coarse-Bed Channels
Contraction scour at bridges spanning coarse-bed channels is evaluated based on mass conservation of both water and transported sediment between a reference channel section near the crossing...

Numerical Simulation of Bridge Abutment Scour Development
This paper reports a project to simulate the development of a local scour hole around a bridge abutment by a computational model. From the prelim inary results obtained, it may be concluded...

HEC-RAS (River Analysis System)
HEC-RAS (River Analysis System) is an integrated system of software, designed for interactive use in a multi-tasking environment. The system is comprised of a graphical user interface...

A Knowledge Based System for the Design of Open Channels
The design of open channel facilities often calls for evaluation of a unique set of physical conditions which do not lend themselves to standard designs and textbook solutions. Consequently,...

Evaluation of Selected Instruments for Monitoring Scour at Bridges in New York
Reliable methods to monitor scour at bridges are needed to ensure public safety and minimize the cost to repair or replace vulnerable bridges. The U.S. Geological Survey, in cooperation...

Design of Guide Banks for Bridge Abutment Protection
As an alternate to designing bridge abutments to withstand the development of the full scour prism predicted by equations currently available for estimating abutment scour, FHWA recommends...

 

 

 

 

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