A combined sewer of circular section is to be designed in a sewage system for a city with a population of 100,000 in an area of 100 hectares. The mean flow of sewage from the city is 250 litre/capita/day. The rainfall intensity in the area is 4 cm/hr. The coefficient of runoff of the area is 0.48. The ratio of peak to average sewage flow is 2.0. The Manning's roughness coefficient is 0.012 and the Hazen-William's coefficient is 85. Using Manning's equation and Hazen- William's expression, determine the gradient of the sewer to carry the peak flow with a velocity of 1.2 m/s.

A combined sewer of circular section is to be designed in a sewage system for a city with a population of 100,000 in an area of 100 hectares. The mean flow of sewage from the city is 250 litre/capita/day. The rainfall intensity in the area is 4 cm/hr. The coefficient of runoff of the area is 0.48. The ratio of peak to average sewage flow is 2.0. The Manning's roughness coefficient is 0.012 and the Hazen-William's coefficient is 85. Using Manning's equation and Hazen- William's expression, determine the gradient of the sewer to carry the peak flow with a velocity of 1.2 m/s.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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