The peak flow of a flood hydrograph caused by an isolated storm was observed to be 100 m³/s. The storm had a duration of 8 hours and total depth of rainfall was 7 cm. If in the above storm, the total rainfall was 9.5 cm in the same duration of 8 hours, then the flood peak discharge is found to be increased by 40%. Considering the base flow as 20 m³/s, the value of -index for the given catchment is cm/h (round off to two decimal places).

The peak flow of a flood hydrograph caused by an isolated storm was observed to be 100 m³/s. The storm had a duration of 8 hours and total depth of rainfall was 7 cm. If in the above storm, the total rainfall was 9.5 cm in the same duration of 8 hours, then the flood peak discharge is found to be increased by 40%. Considering the base flow as 20 m³/s, the value of -index for the given catchment is cm/h (round off to two decimal places).

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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Concept explainers

Probability, risk and uncertainty analysis for hydrological design

It gives a framework that is financially critical for finding the exceptional designs of hydrological systems with a reduced cost in total inclusive of the project cost and the disaster mitigation cost. But there would be hardly any assessment of a decent quality damage function. Hence, errors in demonstrating the hydrologic events, incorrect model parameters, and so on may occur. Here, we will discuss a specific hydrological design that of a detention basin for studying and understanding the risk-based procedure, uncertainties, and probability analysis by following a systematic framework.

Question

The peak flow of a flood hydrograph caused by an isolated storm was observed to be
100 m³/s. The storm had a duration of 8 hours and total depth of rainfall was 7 cm. If in
the above storm, the total rainfall was 9.5 cm in the same duration of 8 hours, then the
flood peak discharge is found to be increased by 40%. Considering the base flow as 20
m³/s, the value of O-index for the given catchment is cm/h (round off to two decimal
places).

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