CIV E 638 - SEDIMENTATION AND RIVER ENGINEERING
FALL 2020
HOMEWORK No. 4:   SEDIMENT TRANSPORT

  1. Calculate the sediment transport rate Qs, in metric tons per day, by the Duboys formula, given the following data: particle diameter ds = 0.8 mm, flow depth d = 1.2 m, channel bottom slope So = 0.001, and channel width b = 18 m. Do the calculation by hand and confirm with ONLINE_DUBOYS.

  2. For the same data of Prob. 1, consider Manning n = 0.022, water temperature T = 20oC, and wash load concentration Cw = 300 ppm. Estimate the mean velocity based on flow depth. Calculate the discharge of sands by the Colby 1964 method. Use ONLINE_COLBY.

  3. For the same data of Prob. 2, consider the measured concentration of suspended bed material (sand) Cm = 550 ppm. Calculate the discharge of sands by the Colby 1957 method. Use ONLINE_COLBY1957.

  4. For the same hydraulic data of Prob. 2, but with ds = 3 mm, calculate the discharge of gravel by the Meyer-Peter formula. Use ONLINE_MEYER_PETER. What would be the gravel discharge is the particle diameter were to be 4 mm? What would be the gravel discharge is the particle diameter were to be 5 mm?