Figure 5.31 Relationship Between Side Slope and K (from Lane, 1953b)

3.

Determine the value of , tractive force, corresponding to the d75 from Figure 5.32.

4.

Based on bed conditions estimate the maximum permissible longitudinal slope by equating the

value of taken from Figure 5.32 to C D So and solve for So in the form:

J

So '

(5.5)

C(D

The influence of the stability of the canal sides on channel slope So must now be checked.

Usually, the side material cannot resist as great a tractive force as the bed because of the

additional effect of gravity.

5.

Knowing size and shape of material, enter Figure 5.33 and estimate the angle of repose.

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