An engineer wanted to determine Q20 when he designed a bridge for a highway. He collected and recorded the measured discharge from a station of the river as shown in the following table. He assumed the flood frequency follows the LP3 distribution. Determine Q20. Values of z used for flood frequency analysis as given as follows ARI 100 2.326 50 2.054 20 1.645 10 1.282 5 0.842 Q (m³/s) Run 1 130 430 130 4 180 80 380 7 280 8 180 230 10 330 2. 3.

An engineer wanted to determine Q20 when he designed a bridge for a highway. He collected and recorded the measured discharge from a station of the river as shown in the following table. He assumed the flood frequency follows the LP3 distribution. Determine Q20. Values of z used for flood frequency analysis as given as follows ARI 100 2.326 50 2.054 20 1.645 10 1.282 5 0.842 Q (m³/s) Run 1 130 430 130 4 180 80 380 7 280 8 180 230 10 330 2. 3.

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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Q1: A hydraulic structure on a stream has been designed for return periods of 50 and ST 100 years. Maximum recorded floods in the stream are given below. Estimate the peak floods for the two return periods above, by using Gumble method. Year 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 Max. 115 128 142 99 79 71 85 102 145 flood, 153 78 50 m³/sec
' The ordinates of a 3-hour UH are given in the following table: Time 3 6 9 12 15 18 21 27 30 (hour) 3 10 30 80 60 50 40 30 10 2 hour UH (m/s) (a) Estimate the area of the basin. (b) Determine the DRH ordinates due to two ER of 2 cm and 3 cm occurring in two successive 3-hour durations each. (c) Estimate the flood hydrograph ordinates if the base flow at time 0 h is 10 m/s and increase to reach 20 m'/s at time of 30h. (d) Estimate the total runoff volume 24
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