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 :     

Press button to
or recalculate

  Your request was processed at  06:11:41 am on June 6th, 2026   [ 260606  06:11:41 ].

Thank you for running   online_scour_froehlich1989   Please call again.   [161214]

Documents in Portable Document Format (PDF) require Adobe Acrobat Reader 5.0 or higher to view; download Adobe Acrobat Reader.