online_scour_jainandfisher:  Calculation of local scour using Jain and Fisher's equation    F = v /(gy)1/2 Vc = Ku y1/6D501/3 Fc = Vc /(gy)1/2 For clear-water scour (F - Fc ≤ 0.2): ys = 1.84 a Fc0.25 (y /a)0.3 For live-bed scour (F - Fc > 0.2): ys = 2 a (F - Fc)0.25 (y /a)0.5 [ SI Units (metric):  ys, y, a, and D50 in m; Ku = 6.19 ] [ U.S. Customary Units:  ys, y, a, and D50 in ft; Ku = 11.17 ] [ F = Froude number; g = gravitational acceleration ] Reference DESCRIPTION      [Sample Input]     [Main page] To determine the bridge scour depth ys, the calculator requires the following input data: Flow depth directly upstream of the pier y1, in m (or ft). Mean flow velocity directly upstream of the pier v1, in m/s (or fps). Pier width in a horizontal direction normal to the flow a (Fig. 1), in m (or ft). Median diameter of the bed material D50, in mm. Fig. 1  Definition sketch.