Example 7. A catchment of 200 hectares area has rainfalls of 7.5 cm, 2.0 cm and 5.0 cm in three consecutive days. The average O index can be assumed to be 2.5 cm/day. Distribution- graph percentages of the surface runoff which extended over 6 days for every rainfall of 1-day duration are 5, 15, 40, 25, 10 and 5. Determine the ordinates of the discharge hydrograph by neglecting the base flow.

Example 7. A catchment of 200 hectares area has rainfalls of 7.5 cm, 2.0 cm and 5.0 cm in three consecutive days. The average O index can be assumed to be 2.5 cm/day. Distribution- graph percentages of the surface runoff which extended over 6 days for every rainfall of 1-day duration are 5, 15, 40, 25, 10 and 5. Determine the ordinates of the discharge hydrograph by neglecting the base flow.

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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Table below gives the time distribution of a rainfall lasting for nine hours. If the direct runoff is 9.3 cm, determine the Ø‐index of the storm and the time of rainfall excess.
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