Question

3. a) A trapezoidal open channel is being designed to convey a discharge of 11.0 m3 /sec. The channel will be excavated into clay and will have the following properties: side slope with m = 1.5, bottom slope of So = 0.001, Manning’s n = 0.022, and bottom width b = 1.0 m. For these conditions is there a risk of channel erosion? b) The earth-works contractor that will carry out the excavation suggests that the side slope angle can be increased to 45o (i.e. m = 1). Comment on the impact that such a change would have on: 1) the required depth of excavation, and 2) the risk of erosion. c) Calculation of the normal depth using Manning’s equation does not consider freeboard. Define the term freeboard, and use equation (28), Chapter 4, to estimate the freeboard required for part a) of this question.

Answer #1

The discharge in a channel with bottom width 3 m is 12 m3 s–1.
If Manning’s n is 0.013 m-1/3 s and the streamwise slope is 1 in
200, find the normal depth if:
(a) the channel has vertical sides (i.e. rectangular
channel);
(b) the channel is trapezoidal with side slopes 2H:1V.
(Answer with steps plz)

A discharge of 4.25 m3 /s occurs within a trapezoidal channel
with a base width of 3m, 3:1 side slopes (i.e. Z = 3), a
longitudinal bed slope of 0.0009 m/m with a Manning’s roughness
coefficient of 0.025 (i.e. sand). State the normal flow depth (yn)
critical flow depth (yc) and the Froude Number of the flowing
water.

3. A trapezoidal channel has a base width b = 8 ft and side
slopes 6H:1V. The frictional slope is Sf = 0.035 and the Manning
roughness coefficient is n = 0.014. Design a channel if channel
discharge is = 15.45 m3 /s using Mannings
equation. The farmer land is 3.482 acre with a
length of 951.43 ft. what is the best length for the grass
waterway?
Depth of channel, d=? (5).
Top width of the channel=? (3)
Freeboard of...

a trapezoidal channel to carry 142 m³/minute of water
is designed to have a minimum cross-section. find the bottom width
and depth if the bed slope is1 in 1200, the side slope at 45° and
chezy's co-efficient =55

A concrete, trapezoidal channel with a 5-m bottom width and side
slopes of 1:1 (H:V) discharges 35 m3/sec. The bottom slope of the
channel is 0.004. A dam is placed across the channel and raises the
water level to a depth of 3.4 m. determine the channel and flow
classification (e.g., M-2, S-1) upstream of the dam and explain
your supporting logic. then compute the water surface profile at
50-m intervals until you reach the hydraulic jump. Use a
spreadsheet...

In a trapezoidal channel with a constant width of b=3 m. and
side slopes of 1:3 (1 vertical, 3 horizontal) and discharge rate of
6 m3 /sec, if the maximum step upward height is z=0.5 m. not to
cause any choking, what is the water depth before and after this
maximum step upward. Draw the water surface profile and specific
energy curve (E vs y) for this flow.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 38 minutes ago

asked 47 minutes ago

asked 47 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago