Question

The manning’s coefficient for a lined trapezoidal channel with a bed slope of 1 in 4000 is 0.014 and it will be 0.028 if the channel is unlined. The area in the case of the lined section is 19.04 m² and for the unlined section is 29.09 m². What percentage of earthwork is saved in a lined section relative to an unlined section, when a hydraulically efficient section is used in both the cases?

a.

24.44 %

b.

34.55%

c.

50%

d.

37.66%

Posted under Irrigation Engineering

Answer: (b).34.55%

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Q. The manning’s coefficient for a lined trapezoidal channel with a bed slope of 1 in 4000 is 0.014 and it will be 0.028 if the channel is unlined. The area in the case of the lined...

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