Laserfiche WebLink
<br />Stream Channel Erosion Protection at Roadway Crossings <br /> <br />Introduction <br /> <br />Role of geomorphic and hydraulic factors in bank protection and bridge <br /> <br />design <br /> <br />Definition of erosion and scour <br /> <br />Types of erosion control (countermeasure) practices <br /> <br />Bridge factors <br /> <br />Geomorphic factors <br /> <br />Flow factors <br /> <br />Typical flow and channel characteristics <br /> <br />Hydraulic properties and channel geometry <br /> <br />Changes in channel capacity with time <br /> <br />Determination of Mannings roughness coefficient <br /> <br />Channel bed scour <br /> <br />Effects of bridges on streamflow and the channel <br /> <br />Long-term trends to equilibrium channel size <br /> <br />Lateral migration of lowest point in channel bed <br /> <br />Flow constriction related to skewed piers <br /> <br />Longitudinal extent of general scour <br /> <br />Depth of general scour at bridge sites <br /> <br />Bank protection measures <br /> <br />Estimation of median (D50) stone size based on shear stress <br /> <br />Preliminary approach to estimating median (D50) based on velocity <br /> <br />Side slope <br /> <br />Depth of toe <br /> <br />Example bank protection design <br /> <br />Selected references <br />