Hydraulic Design of Highway Culverts - DOT On-Line Publications

ELhf
ELhi
ELho
ELht
ELO
ELsf
ELSO
ELt
ELtw
GLOSSARY (Cont.)
Headwater elevation required forflow to pass face section in face control, m (ft)
Headwater elevation required for culvert to pass flow in inlet control, m (ft)
Headwater elevation required for culvert to pass flow in outlet control, m (ft)
Headwater elevation required for flow to pass throat section in throat control, m (ft)
Invert elevation at outlet, m (ft)
Stream bed elevation at face of culvert, m (ft)
Stream bed elevation at outlet of culvert, m (ft)
Invert elevation at throat, m (ft)
Tailwater elevation, m (ft)
f Darcy resistance factor
Fr Froude number
FALL Depression of inlet control section below the stream bed, m (ft). (Measured
from stream bed to face invert for culvert, to throat invert for culvert
with tapered inlet.)
G The number of different materials (roughnesses) in the perimeter of a conduit
with composite roughness
9 Acceleration due to gravity, 9.81 m/s/s, (32.2 ft/s/s)
HGL Hydraulic grade line
h Height of hydraulic grade line above centerline of orifice, m (ft)
hf Friction head loss, m (ft)
ho Height of hydraulic grade line above outlet invert, m (ft)
ht Height of tailwater above crown of submerged road, m (ft)
H Sum of inlet loss, friction loss, and velocity head in a culvert, m (ft)
HL Total energy required to pass a given discharge through a culvert, m (ft)
Hb Head loss at bend, m (ft)
HC Specific head at critical depth (dC + VC 2 /2g), m (ft)
He Entrance head loss, m (ft)
Hf Friction head loss in culvert barrel, m (ft)
H9 Head loss at bar grate, m (ft)
Hj Head loss at junction, m (ft)
Hl Friction head loss in tapered inlet, m (ft)
Exit head loss, m (ft)
Ho
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