Determine the value of o for the rainfall hyetograph shown. Assume the deplh of direct runoffis 2.5 in.t(hr)The following data are from the 2.15-acre watershed W-15, Cherokee, Oklahoma, for thestorm of November 16, 1964. Assume that baseflow equals 0 and all rainfall prior to the startof runoff is initial abstraction. Determinc the distribution of rainfall excess using the phi-indexmethod. [Note: Rainfall values give the average intensity over the interval; runoff values areordinates.]HyctographHydrographTime ofRateTime ofRateTime ofRateDay(in/hr)Day(in./hr)Day(in./hr)05300.0007320.000008260.54306300.0107360.001408280.4180.3220.2180.1520.1040.090407300.0007380.004908300745080004407540.004908340.1207560.00960838080519207580.0228084208 1019208000.0441090008 151.2008020.059709100.0654082008250.0972092009300.04900.03930.7208040.3608060.12708300.240808021809400.0266084509000.1208090.33509500.01550.160810049410000.012409450.0008120.68710300.012409500.2408140.80710560.00960.00490.00490.00140.0000100008160.000.160.030.9371110101508171.051130103508200.871122008240.6681350

Determine the value of o for the rainfall hyetograph shown. Assume the depth of direct runoff is 2.5 in. t(hr) The following data are from the 2.15-acre watershed W-15, Cherokee, Oklahoma, for the storm of November 16, 1964. Assume that baseflow equals 0 and all rainfall prior to the start of runoff is initial abstraction. Determinc the distribution of rainfall excess using the phi-index method. [Note: Rainfall values give the average intensity over the interval; runoff values are iin./hr)

Determine the value of o for the rainfall hyetograph shown. Assume the depth of direct runoff is 2.5 in. t(hr) The following data are from the 2.15-acre watershed W-15, Cherokee, Oklahoma, for the storm of November 16, 1964. Assume that baseflow equals 0 and all rainfall prior to the start of runoff is initial abstraction. Determinc the distribution of rainfall excess using the phi-index method. [Note: Rainfall values give the average intensity over the interval; runoff values are iin./hr)

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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The rainfall intensity for each 20 min period are given below for a storm. The direct runoff from the basin is 2.5cm 20 MINUTES RAINFALL RAINFALL 1 2.5 2 5 a) What is the total storm rain? cm b) What is the Phi Ø index for the basin? 3 6.5 _cm/hr 4 3.5 5 1
Analysis of rainfall and runoff records for a certain storm over a basin (of area 3210 km²) gave the following data: Rainfall for successive 2 hr periods: 2.5, 6.5 and 4.5 cm/hr. Direct surface discharge at the concentration point for successive 2-hr periods: 400, 1200, 4500, 7700, 12000, 10220, 8260, 3900, 838 and 400 m’. Derive the unit hydrograph for the catchment area.
Net Storm Rainfall Example 2-1 Rain falls as shown in the rainfall hyetograph (intensity Vs. time) in Fig. E2-1 (a). The o index for the Storm is 0.5 in./hr and is constant over 5 hr. Plot the net rainfall on the hydrograph (flow vs. time) given in Fig. E2-1 (a). Determine the total volume of runoff and the watershed area. 1cfs = 1.008 ac-in/hr 2.0 1.5 1.0 0.5 1 3. 4 Time (hr) 700 600 500 400 300 200 100 4 8 12 16 20 24 Time (hr) Time (hr) Q (cfs) Volume (cfs-hr) 0-2 2-4 4-6 6-8 8-10 10-12 12-14 14-16 16-18 18-20 20-22 22-24 24-26 16 Q (cfs) iT (in./hr)
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