Hydraulic Design of Highway Culverts - DOT On-Line Publications

d/D d A/BD A R/D R
0.65 13.0 0.5537 332.2 0.3642 7.28
0.70 14.0 0.6013 360.8 0.3781 7.56
0.75 15.0 0.6472 388.3 0.3886 7.77
0.80 16.0 0.6908 414.5 0.3950 7.90
0.85 17.0 0.7313 438.8 0.3959 7.92
0.90 18.0 0.7671 460.3 0.3870 7.74
0.95 19.0 0.7953 477.2 0.3649 7.30
1.00 20.0 0.8108 486.5 0.3060 6.12
Complete Water Surface Computations (see attached calculation sheet).
HW = specific head (H) + ke (V²/2g)
Neglecting approach velocity head :
for Q = 5,500 ft³/s:
HW = 18.004 + (0.5)(3.208) = 19.6 ft
ELho = 220 + 19.6 = 239.6 ft
for Q = 7,500 ft³/s:
HWf = 22.627 + (0.5)(3.89) = 24.6 ft
ELho = 220 + 24.6 = 244.6 ft
SUMMARY:
DESIGN Q:
CHECK Q
ELhd ELhi ELho
240.0 238.0 239.6
ELha ELhi ELho
245.0 242.6 244.6
This culvert design meets the requirements stated in the problem.
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