CIV E 530 - OPEN-CHANNEL HYDRAULICS
SPRING 2007
HOMEWORK No. 8

  1. (50 percent) A steep channel flows into a milder steep channel, generating a S3 water-surface profile in the downstream channel.

    It is desired to calculate the length of the S3 water-surface profile.

    The hydraulic data is the following: Q = 5 m3/s; b = 2 m; z = 1.5; and n = 0.013.

    The u/s channel slope is 0.02; the d/s channel slope is 0.006.

    1. Run CHANNEL in http://onlinecomp.sdsu.edu to calculate the upstream and downstream normal depths.

    2. Run DIRECTSTEP in http://onlinecomp.sdsu.edu to calculate the length of the S3 water-surface profile.

    3. Report outputs from CHANNEL and DIRECTSTEP.

  2. (50 percent) How much longer (or shorter) would the water-surface profile have to be if the d/s channel slope is 0.004 instead?