VAC3041 Assignment 2 (RORB)
Aim: To determine the design hydrograph at a bridge site using RORB Design Brief:
The accompanying diagram is a map of the upper Deep Creek rural catchment with sub-areas A, B, C, D, E and F marked in.
The Client (The Road Authority) wishes to replace the old timber road bridge that crosses Deep Creek 200m south of the confluence with Boyd Creek. The new bridge is to be designed for a 50 year ARI flood.
Close to the bridge site there is a stream gauging station (O), which has been in place for eight years, and there is a telemetered pluviometer located at Romsey (?).
Tasks: (Each student must assume a team leadership role in the completion of at least one of these Tasks) (i) Using RORBWin, prepare a catchment file using the Graphical Editor and the following data.
Areas in km2 : A = 114.4, B = 86.9, C = 67.5, D = 81.7, E = 62.5, F = 75.6
Make clear any assumptions made.
Prepare a storm file and use it to calibrate the catchment. Use the storm file provided on page 2 based on a heavy 50 hour storm that fell over the catchment in 1996, which includes the hydrograph of runoff recorded at the Darraweit gauging station. The FIT run ‘statistics’ window must be included in the report (See Lec.10, p82).
(ii) Prepare a storm file solely for the purpose of estimating the time of concentration for the catchment.
Based on the estimate for time of concentration, prepare a design storm file based on a standard temporal pattern (see p2) and use RORBWin to produce the hydrograph of runoff at the bridge site.
(iii) Prepare two other design storm files based on standard temporal patterns (to be specified by the Lecturer) for the purpose of determining the critical storm duration and the critical design flow rate for the design of the bridge.
Determine the peak design flow rates for these storms and report the results for all three storms to the Lecturer.
(iv) Prepare a group report containing:- College assignment cover sheet, title page, executive summary, table of contents with page numbers, this project brief, all relevant computations and results (including graphical outputs) set out clearly under meaningful sectional headings, including brief but comprehensive explanations of the methods employed and all assumptions made, and a conclusion. All work is to be performed to a professional standard.
Students are to work in groups of three maximum, share the tasks equally and thoroughly check each other’s work. Each student is to take full responsibility for all the work submitted.
Note: The Table of Contents must show the name of the student who played a leading role in the completion of each Task or the preparation of the bulk of the content of the report based on that Task.
Page 1
Storm File
50 HRS, 8PM 1996
FIT
C TIME INC IS 1.0HR, CALCS FOR 100 INCS, 1 BURST, 1 PLUVIS, R/F NOT UNIFORM 1.0,100,1,1,1,-99
C BURST FROM 0 TO 50
0,50
DARRAWEIT GUIM
1.2,3.9,3.6,2.9,3.0,2.6,3.2,2.9,3.8,3.9,4.6,5.2,4.2,3.6,3.0,2.7,2.8,2.6
2.2,2.2,3.2,3.4,3.3,4.8,4.4,2.7,2.7,3.6,3.6,1.9,1.6,1.2,1.1,1.2,1.1,0.7
0.9,0.9,0.7,1.2,0.5,0.3,0.4,0.6,0.6,0.2,0.2,0.2,0.1,0.1,-99, mm/hr
C RAINFALLS ON SUB AREAS (mm)
117,113,111,110,111,108,-99
C HYDROGRAPH DATA
1,100,-99
DEEP CREEK AT DARRAWEIT
0.46,5.46,15.46,20.4,26.5,30.0,36.0,35.0,40.0,49.0,66.0,83.0,96.0,110.0
120.0,110.0,101.0,96.0,94.0,90.0,114,123,126,128,130,135,138
142,151,155,152,142,138,130,125,117,113,108,106
102,98.0,96.1,93.7,91.4,90,85,80,75,70,68
66,65,60,57,55,54,53,52,51,48,45
44.50,43.15,39.81,36.73,32.04,31.53,30.24,27.17,24.30,21.63,20.37
19.16,18.0,16.88,15.80,14.77,13.79,12.85,12.85,11.95,11.09,11.09
10.27,10.27,9.49,8.75,8.75,8.05,7.39,7.39,6.76,6.76,6.76,6.76
6.16,6.16,6.16,6.16,6.16,-99, cumecs
Standard temporal patterns for Zone 1:
Isohyetal Map (1996 Storm)
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