Question

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QUESTION 1 A 10-inch PVC (n-0012) sewer pipe is laid on a slope of 0.28%. Determine the capacity O a. 0.61 cfs O b.0.83 cfs O 1.26 cfs O d.1.81 cfs O e 3.11 cfs QUESTION 2 Calculate the Hydraulic Radius for a rectangular channel that has a bottom width B-3t flow of 2 feet a Manning's n value of 0 022, and bottom slope of İ%, and a depth of O b.1.50 ft O c 2.22 ft O e 3.75 ft

Answer 1

n = 0.012, S = 0.0028 dia of pipe(D) = 10/12 feet = 5/6ft implies Capacity(q) = 1/n Ax(R)^2/3 S^1/2 A = n/4 d^2 = n/4 times (5/6)^2, R = D/4 = 5/6/4 = 5/24 implies Q = 1/0.012 times[n/4 times(5/6)^2]times[5/24]^2/3 times (0.0028)^1/2 implies Q = 0.845 Cfs almostequalto (b) A is Hydraulic Radius per Rectangular channel B = 3ft, y = 2ft r = A/P A = B times y = 3 times 2 = 6ft^2 P = b + 2y = 3 + 2 times 2 = 7ft implies R = A/P = 6/7 = 0.857 ft implies Hydraulic Radius(R) = 0.86ft