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<br />42 TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS
<br /> 8.IN DEGREES e
<br />1.25 90 80 70 60 50 40 30 20 10 0
<br />1.20
<br /> "-
<br /> "-
<br />1.15
<br />....~ "-
<br /> "-
<br />1.10 /
<br /> / ,
<br />1.05
<br /> "'-
<br />1.00
<br />0 0,10 0,20 0,30 0.40 0,50 0,60 0,70 0,80 0,90 1.00
<br /> COSINE 8
<br />Figure 24.-Voriation of discharge coefficient with wingwoll onglel types 1,2, and 3 flow in box culverts with
<br /> wingwall set flush with sloping embankment.
<br />
<br />
<br />
<br />following list presents values of kL for various
<br />values of L.ID,
<br />
<br />L,ID " L,ID " ,
<br />--
<br />0, 00 1. 00 0,0 1.00
<br />,01 ,99 ,1 ,92
<br />,02 ,98 ,2 ,92
<br />,03 I ,98 I ,:1 ,92
<br />,04 .97 ,4 ,91
<br />,05 .96 i .il .91
<br />,(16 .95 ,6 .91
<br />.07 ~ ,7 .91
<br />,,;:>.08 ,8 ,90
<br />I ,09 ,9 . no
<br />,10 .92 51.0 .90
<br /> , ,
<br />
<br />Concrete pipes with beveled end
<br />The discharge coefficient for projecting en-
<br />tmnces for concrete pipes with a beveled end
<br />i~ the same as for flush entrances.
<br />
<br />Mitered pipe set Flush with sloping embankment
<br />
<br />The discharge coefficient for mitered pipes
<br />set flush with a sloping embankment is a
<br />fundion of the ratio of headwater height to
<br />pipe diameter and can be determined from
<br />figure 25.
<br />For a projecting mitered pipe with a thin
<br />wall (like corrugated metal), adjust the dis-
<br />charge coefficient. in t.he same manner as any
<br />other projecting barrel. Do not adjust for round-
<br />ing or beveling.
<br />
<br />
<br />
<br />Types 4 and 6 flow
<br />
<br />Flush setting in vertical headwall
<br />
<br />-e
<br />
<br />Box or pipe culverts
<br />Select the discharge coefficient for box or
<br />pipe culverts set flush in a vertical headwall
<br />from table 5. This includes square-ended pipes
<br />or boxes, corrugated pipes, corrugated pipe-
<br />arches, corrugated pipes with a standard
<br />conical entrance, concrete pipes with a beveled
<br />or bellmouthed end, and box culverts with
<br />rounded or beveled sides.
<br />
<br />Table 5.-Discharge coefficients for box or pipe culverts set
<br />flush in a vertical headwall; types 4 and 6 flow
<br />--I
<br />('
<br />
<br />rlfJ,w/b,wID,orrllJ
<br />
<br />l-
<br />m!
<br />
<br />0.84
<br />,88
<br />. HI
<br />.04
<br />,96
<br />.97
<br />.H8_J
<br />
<br />o __n___n_
<br />,02_____ __nuu_____, ____,_u
<br />,04_uu__ _______
<br />,,06___ ______u_uu,___,
<br />',08_ _ _ __ _ _ _ _ _ _ _ u _ u n _ _ u _ _ _ __
<br />,10____________________ ________
<br />.12__________________________
<br />
<br />Tbe discharge coefficient for flared pipe end
<br />sections is 0,90 for all diameters and all values
<br />of (hl-z)(D,
<br />
<br />-e
<br />
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