online_scour_hec18:  Calculation of bridge scour using the HEC-18 formula   
Formula:

Fr1 = v1/(g y1)1/2

ys /y1 = 2 K1 K2 K3 (a / y1)0.65 Fr10.43

[ SI Units (metric):  ys, y1, a, and L in m ]
[ U.S. Customary Units:  ys, y1, a, and L in ft ]
[ Fr = Froude number; g = gravitational acceleration ]

Reference:

Evaluating Scour at Bridges,
FHWA Hydraulic Engineering Circular No. 18,
 Fifth Edition, 2012.

INPUT DATA:      [Description]     [Sample Input]

Select:      

Flow depth y1 :      

 

Flow velocity v1 :      

 

Pier width a :      

 

Pier length L :      

 

Angle of attack θ of the flow (degrees):      

 

Pier nose shape:      

Bed condition:      

OUTPUT:

System of units:  SI units (metric)

Pier nose shape:  Square nose

Bed condition:  Clear-water scour

♦  Scour depth ys :     

Press button to
or recalculate

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