online_scour_froehlich1989:  Calculation of abutment scour using the Froehlich 1989 equation   
Formula:

Fr = v /(gya)1/2

(ys / ya) = 2.27 K1 K2 (L' / ya)0.43 Fr 0.61 + 1

[ SI Units (metric):  ys, ya and L' in m ]
[ U.S. Customary Units:  ys, ya 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 units:      

Flow depth y1 :      

 

Flow velocity v1 :      

 

Length of flow obstructed by the embankment L' :      

 

Angle of embankment with the flow θ (degrees):      

 

Select abutment shape:      

OUTPUT:

System of units:  SI units (metric)

Abutment shape:  Vertical wall

♦  Scour depth ys :     

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