OUTLET WORKS STILLING BASIN FOR TEXARKANA DAM …hydraulic-jump type stilling basin. Design capacity...

711'1' I (/fJ34 no.Jr 34~ '£0 CORPS OF ENGINEERS, U. S. ARMY

OUTLET WORKS STILLING BASIN FOR TEXARKANA DAM

SULPHUR RIVER,TEXAS

HYDRAULIC MODEL INVESTIGATION

TECHNICAL MEMORANDU M NO. 2-346

WATERWAYS EXPERIMENT STATION

ARI4Y· MRC YIC KSBUR~. MIS$.

VICKSBURG, MISSISSIPPI

JUNE 1952

PROPERTY o:F u. s.--"i.Rttr--....._ OF.FI OE CHIEF O•F ENG!IiNlEIIilllS LIBRARY

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4. TITLE AND SUBTITLE Outlet Works Stilling Basin for Texarkana Dam, Sulphur River, Texas:Hydraulic Model Investigation

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7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Corps of Engineers,Waterway Experiment Station,3903 HallsFerry Road,Vicksburg,MS,39180

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Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18

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FRONTISPIECE . Texarkana Dam Control Struct ures

PREFACE

Model investigations of the outlet works stilling basin for

Texarkana Dam were authorized by the Chief of Engineers in the third

indorsement to a letter to the Division Engineer, Lower Mississippi

Valley Division, dated 10 May 1949. The model studies were conducted

during the period May 1949-June 1950 in the Hydraulics Division of the

Waterways Experiment Station by Messrs. T. J. Buntin, John N. Strange,

and C. M. Wright, under the general supervision of Messrs. F. R. Brown

and T. E. Murphy.

Messrs. E. J. Williams, J. E. Sanders, C. L. Sumrall, Jr., and

i

F. B. Toffaleti, engineers of the Lower Mississippi Valley Division,

visited the Experiment Station at frequent intervals during the course

of the study to discuss testing procedures and to correlate test results

with design work being accomplished concurrently.

CONTENTS

PREFACE •

SUMMARY •

PART I: INTRODUCTION •

The Prototype • Purpose of Model Analysis •

PART II: THE MODEL •

Description • Scale Ratios

PART III: TESTS AND RESULTS

Original Design • Alterations to Original Design Recommended Design

PART IV: CONCLUSIONS AND RECOMMENDATIONS •

PHOTCGRAPHS 1-16

PlATES 1-14

iii

i

v

1

1 2

3

3 4

5

5 7

14

17

SUMMARY

The outlet works stilling basin for Texarkana Dam was studied on

a 1:25-scale model to insure adequacy of the basin in reducing the

velocity of flow issuing from the twin conduits.

v

Initial tests indicated the necessity for revision of various

stilling basin elements. Energy of flow from the conduits operating

singly, or in combination, was not diminished as the flow passed through

the stilling basin. Flow concentrated in areas adjacent to t11e splitter

wall and had upstream direction adjacent to the outside basin walls.

The desired performance of the stilling basin was secured by use

of warped transition sections downstream from the conduit exit portals,

elimination of the stepped apron, and reduction of 3 ft in the height

of the splitter wall. The elevation of the stilling basin and height

of end sill were not changed.

OUTLET iVORKS STILLING BASIN FOR TEXARKANA DAM

SULPHUR RIVER, TEXAS

Hydraulic Model Investigation

PART I : INTRODUCTION

The PrototYIJe

1. Texarkana Dam is an earth-fill

dam under construction on the Sulphur l .(.,_ ~ i~

River approximately 9 miles southwest of

Texarkana, Texas (fig. 1) . It will be

approximately 100 ft high and 18,500 ft

l ', I 0 .", . ...

long . The reservoir created by the dam

will have an area of 119,700 acres at

spillway crest elevation of 259 . 5* and

a total storage capacity of 2, 654, 300

acre-ft . The reservoir will extend

up the Sulphur River approximately

I

SCALE IN MlLES .. . .. e:::::c::JECJS

60

I.ITTLE ROCK~

1t~T0tt 0

MONROe'

40 miles . The reservoir will be Fig . 1 . Vicinity map

20, 300 acres in area and will store 145 , 300 acre-ft at the conservation

pool elevation of 220 .

2. Normal f lmv regulation will be accomplished by means of four

slide gates located within the intake structure of the outlet works .

Flow from the intake structure will pass through two circular conduits

* All elevations are in feet above mean sea level .

2

20 ft in diameter and approximately 480 ft in length, discharging into a

hydraulic-jump type stilling basin. Design capacity of the outlet works

is 281 000 cfs. Details of the stilling basin as originally designed and

as revised are shown on plates 1 and 9, respectively.

3. Flows exceeding the storage capacity of the reservoir will pass

over an uncontrolled chute-type spillway located in the right abutment of

the dam (see frontispiece). The spillway, with crest at elev 259.5, is

designed to pass a maximum discharge of 66,800 cfs under a head of 19.2

ft. High velocity flow will be reduced at the toe of the spillway by

means of a hydraulic-jump type stilling basin.

Purpose of Model Analysis

4. Previous experience has indicated that satisfactory stilling

basin performance is difficult to procure where symmetry of basin dimen

sions is not maintained about the center line of each conduit. The

general purpose of the model studies, therefore, was to examine the per

formance of the stilling basin of the outlet structures as originally

designed and to make such revisions as appeared necessary to effect

economies or improve flow conditions.

3

PART II: THE MODEL

Description

5. The model of Texarkana Dam outlet works was constructed to

an undistorted scale ratio of 1:25 (photograph 3) and reproduced approx

imately 400 ft of the conduits, the complete stilling basin and about

300 ft of the exit channel. 'I'he intake structure and upstream transi

tion section were not reproduced.

6. The stilling basin area was constructed of concrete and wood

to facilitate alterations. The twin conduits were fabricated of sheet

metal. ~fo metal gates with air vents were located at the upstream end

of the model conduits at the junction with the headbay of the model for

regulation of flow and simulation of prototype conditions.

7. The water used in the operation of the model was supplied by

a circulating system, the measurement of discharge being accomplished

by use of a venturi meter installed in the inflow line. Flow from the

supply line was discharged into the headbay where it was stilled by

baffles prior to its entrance into the conduits. The tailwater eleva

tion in the exit area was controlled by means of an adjustable tailgate.

After passing over the control tailgate the water flowed through a

return line back to the sump from which it was originally pumped.

8. Steel rails set to grade along each side of the model provided

a reference plane for use of all measuring devices. Average water

surface elevation was measured by means of a portable sounding rod

placed on an angle-beam supported by the rails. Velocities were

measured by means of a pitot tube arranged in a bracket to enable

4

measurements to be made for any direction of flow. Flow conditions were

recorded by means of photographs. The bed of the exit channel was molded

in sand for scour tests, and was capped with cement mortar for velocity

measurements. All scour tests were of one hour duration, model time.

Scale Ratios

9. The accepted equations of hydraulic similitude, based on the

Froudian relationships, were used to express the mathematical relation-

ships between the dimensions and hydraulic quantities of the model and

the prototype. General relationships for the transference of model data

to prototype equivalents, or vice versa, are presented in the following

table:

Dimension Ratio Scale Relationship

Length L:r 1:25

Area Ar = Lr-2 1:625

Velocity Vr = Lrl/2 1:5

Discharge Qr = Lr-5/2 1:3,125

Roughness Dr = lrl/6 1:1.710

5

PART III: TESTS AND RESULTS

10. It was necessary in all tests to adjust the disch~rge in

accordance with the computed pool-discharge relations furnished by repre-

sentatives of the Lower Mississippi Valley Division, since the intake

structure was not reproduced in the model, Discharge conditions for

'\vhich data were desired are tabulated below:

Discharge, cfs

5,000 10,000 10,000 10,000 10,000 14,000 15,000 18,000 28,000

Pool Elevation

259.5 259.5 242.5 222.2 259-5 259·5 259.5 259.5 259.5

Tailwater Elevation

203.95 210.0 210.0 210.0 212.3 212.3 212.45 213.1 214.7

Discharges of 10,000 and 18,000 cfs with their respect~ve pool and tail-

water conditions were considered most important for investigation. Dis-

charges in excess of 18,000 cfs lvill be infrequent, although the outlet

structures lvere designed for a maximum capacity of 28,000 cfs. A dis-

charge of 14,000 cfs with only one conduit in operation was most critical

for investigation of effect of splitter-wall elevation.

11. Test data are not presented for many of the alterations tried

in the model, because if an alteration obviously made no improvement in

flow conditions it was changed immediately without further investigation.

Original Design

12, Tests of the original design stilling basin (plate 1) indi-

cated unsatisfactory flow conditions for all discharges. Although flow

6

was symmetrical about the center line of the stilling basin, strong down-

stream currents existed along the splitter wall whereas currents along

the spray walls were upstream in direction (photographs 1 and 2) . Condi-

tions existing within each half of the stilling basin are also shown

diagrammatically in fig . 2 . The upstream currents along the spray walls

CONCENTRATED JET

~~~- -----~

CONFINING FORCES

Fig . 2. Flow in stilling basin of original design

actually helped confine the high velocity jets issuing from the conduits

against the splitter wall . Thus little or no reduction in velocity was

effected as flow passed through the stilling basin. The shaded portion

of the basin shm-rn in the figure cont ributed nothing toward improving

basin performance . The stepped portion of the apron appeared to have

little or no effect oo flow distribution wit hin the stilling basin.

13. Prior to t he start of each scour test t he bed of the exit

channel was molded to elev 180. Scour caused ·by the flow conditions de-

picted in photographs 1 and 2 are shown on photographs 3 and 4. These

data indicate that the upstream flmv along the spray walls was of suffi-

cient magnitude to transport bed material from t he exit area into the

stilling basin, The lack of appreciable scour downstream from the end

sill is an indication that the high velocities were confined to surface

flow.

7

14. Velocities measured over the cross section of the basin at the

end sill indicate the extent and magnitude of the currents in the stilling

basin for various discharges (plates 2-3). Downstream flow was confined

to the center third of the stilling basin and varied in velocity from

about 5 ft per sec at the end sill to 13 ft per sec at the water surface

for a discharge of 18,000 cfs.

Alterations to Original Design

Baffle piers

15. Initial efforts to improve stilling basin performance involved

alterations to the height, shape, and location of baffle piers. Baffle

piers 4 and 8 ft in height and either stepped or vertical were investiga

ted. The baffle piers, for the most part, were located in rows perpendic

ular to the splitter wall; however, one test was conducted wherein the

baffle piers ivere slanted diagonally across the halves of the stilling

basin, i.e., the baffle pier adjacent to the splitter wall was farther

upstream than the baffle pier in the same row adjacent to the spray wall.

Elimination of all baffle piers to study the absolute effect of the piers

indicated that they were of some use in reducing the velocity of flow

passing through the stilling basin. Comparison of the scour data (photo

graph 5) obtained after removal of the baffle piers with the scour data

(photograph 3) obtained with the basin of original design indicates an

increase in scour resulting from elimination of the baffle piers. Tests

8

of other alterations to the baffle piers indicated no improvement in basin

performance over that obtained with the basin of original design. The

high velocity flow issuing from the conduits pushed the tailwater farther

downstream as tne baffle piers were reduced in height or were moved down

stream. Therefore it was decided to retain the original design of baffle

piers, although flow was still confined to the middle third of the

stilling basin.

Horizontal apron and end sill elevation

16. The horizontal apron and end sill were raised 5 ft to elevation

180 and 185, respectively, in an effort to improve flow distribution in

the stilling basin. The effect of this alteration on basin performance

was negligible, although velocities over the end sill were increased

(plate 4). However, the magnitude of velocities over the end sill was

less than that considered likely to cause erosion of the exit area. A

10-ft increase in the height of the end sill (top elevation 190) increased

velocities (plate 4) and was considered undesirable. Therefore, an ele

vation of 180 was tentatively adopted for the horizontal apron in conjunc

tion with a 5-ft-high end sill. Flmv- conditions were still about the

same as those observed in the stilling basin of original design. The

stilling basin was later returned to its original elevation to maintain

the end sill at the same elevation as the exit channel downstream.

Sloped apron

17. Alterations to the angle of the steps forming the sloping por

tion of the basin floor failed to improve flow conditions. Velocities at

the end sill, with the angle of flare of the steps with respect to the

spray walls increased from 90 to 120 degrees (fig. 3), are shown on plate 5.

9

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Fig. 3. Stilling basin with i ncreased angle of flare of steps

Elimination of the steps ent i r ely by molding a smooth curve t o t he equa

tion of x2 = -270Y (f ig . 4) had no effect on f low conditions . Thus ,

eliminat ion of the st eps from the stil l i ng basin design appeared war-

rant ed. Although flovT conditions were not affected by such revision,

some economies i n construct i on could be made .

~--------~----------- 200'--------------------~ 1----<o'---f----JIIJ.S'---f-- ti.S' 6' IT' -fo-----W------>!f--IS'

Fig. 4. Sti lling basin with steps replaced by smooth curve

Stilling basin width

18. Efforts were directed towar d el imination of t he eddies adja-

cent t o the spray walls by decreasing the width of the basin, inas~uch as

neither alterations t o .t he baffle piers nor to the basin f loor effected

10

the desired improvement in flow conditions. Accordingly, the width of

the stilling basin at the end sill was decreased from 127 to 82.5 ft.

The resulting flow conditions (photograph 6) approached those desired.

Eddy action adjacent to the spray walls was almost eliminated and better

flow distribution within the basin resulted. Although velocities over

the end sill were increased only slightly for a discharge of 10,000 cfs,

velocities for a discharge of 18,000 cfs were considered excessive

(plate 6). Therefore efforts to secure the desired flow distribution by

reducing the width of the stilling basin were abandoned.

Deflector blocks at conduit exit portal

19. Efforts vrere made to direct the jets issuing from the conduits

away from the splitter wall, since alteration of the stilling basin proper

did not accomplish the desired results. The four types of deflector

blocks investigated are shown in fig. 5. Use of the deflector blocks ac

complished the desired flow distribution and stilling basin performance,

and appeared to give the desired results (see plate 7). However, it was

realized that the blocks -vrould be subject to damage by debris and that a

similar device to deflect the high velocity jet should be devised.

Revision of exit portal

20. Efforts to secure uniform flow distribution in the stilling

basin included constriction of the conduit exit portal and use of a

humped floor starting within the portal and extending into the stilling

basin. None of these efforts was successful. Design engineers of the

Lovrer Mississippi Valley Division were of the opinion that diversion of

the high velocity jets should be accomplished -vrithin the confines of the

stilling basin rather than I<Tithin the conduit proper.

TYPE A

TYPE C

PARTIAL PLAN AND PROfiLE OF ST ILLING BASIN

Transit ions at conduit exit :portals

TYPE B

TYPE ·D

Fig. 5

Deflector blocks

21 . The lengt h of t he stilling basin was i ncreased 50 ft a t t he

11

conduit exit portals t o :provide additi onal l ength for deflection of the

12

high velocity jets. This increase in length of stilling basin was accom

plished by shortening the conduits 50 ft. The stilling basin apron and

end sill also were lowered to their original elevations of 175 and 180,

respectively, at the request of engineers of the Lower Mississippi Valley

Division. This was done to maintain the end sill at the same elevation

as the exit channel downstream. 'I'he use of broad-crested weirs 5 to 7. 5

ft in height and located about 50 ft downstream from the conduit exit por

tals was first investigated. Resulting flow conditions were considered

unsatisfactory (photograph 7). Impact of flow on the weirs was excessive

and the discharge capacity of the conduits was reduced. Wedge-shaped

fillets of varying slopes adjacent to the splitter wall (fig. 6) were next

Fig. 6. Wedge-shaped fillets adjacent to splitter vrall in stilling basin

13

investigated. Use of t hese fillets resul ted in a marked improvement

i n flow conditions (photograph 8) . A good hydraulic jump obtained and

flow appeared evenly distributed across the stilling basin (plate 8 ) .

Erosion test data for f l ows of 10,000 and 18,000 cfs are presented i n

photograph 9. A third scheme was investigated, despite the fact that the

desired flovr conditions had been obtained, vrhich involved a 5- ft superele-

vation of the apron floor immediately downstream from t he exit portal

(fig. 7 ). The radius of curvature of the spray vralls in the immediate

vicinity of the conduit exit portals also was increased from 100 to 575 ft .

SECTION SO' DOWNSTREAM OF TUNNEL EXIT

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ELEVATION A LONG FACE OF SPLITTER WALL

Fig . 7 . Apron floor superelevated 5 ft immediately downstream from port als

The resulting flow conditions (photograph 10) were similar t o those ob -

served vrit h the "'vedge- shaped fille t . A good hydraulic jump obtained and

flow appeared unifo:i:·mly di str ibuted. Since t he superelevated transition

results in a continuously submer ged deflec t ing surface, it is believed

superior to the wedge - shaped fillet for installation in the prototype

14

structure. Attempts to reduce the over-all length of the stilling basin

from 250 to 200 ft were unsuccessful.

Splitter wall

22. Tests were made of various alterations to the splitter wall in

an effort to effect economies in its construction. One test also was con

ducted with the splitter wall eliminated entirely. Elimination of the

splitter wall destroyed all evidence of jump action and a large amount of

scour in the exit area (photograph 11) resulted. Consequently, the

splitter wall was considered an important part of the stilling basin.

Alterations to the wall were investigated involving variation of the top

elevation of the downstream portion of the wall from 213 to 198, and

variation of the length of the wall. Tests of these alterations, with

both conduits in operation, indicated the possibility of reducing the top

elevation to 198 and shortening it to the second row of baffle piers.

However, representatives of the Lower Mississippi Valley Division requested

that the wall be designed to provide good stilling basin performance for a

discharge of 14,000 cfs through one conduit. It was decided, on the oasis

of general hydraulic behavior of flow within the stilling basin and the

maximum depth of scour noted in the exit area, that the lower end of the

splitter wall should be at elevation 210. It also was determined from

these data that the shortest length possible was 200 ft; thus, the wall

was terminated 50 ft upstream from the end sill.

Recommended Design

23. The stilling basin design encompassing all of the most satis

factory elements derived from studies of the alterations previously

15

described is shown in photograph 12 and plate 9. Comparison of the

physical features of the recommended design of stilling basin with those

of the original design (plate 1) indicates the following:

a, The over-all length of stilling basin was increased 50 ft by reducing the length of the conduits.

b. A warped transition vrith a 5-ft superelevation of the apron floor at the conduit exit portals was used to secure the desired flow distribution.

c. The radius of the curved spray walls near the exit portals was increased from 100 to 575 ft.

d, The stepped portion of the apron was replaced with a smooth trajectory curve •,

e. The downstream portion of the splitter wall was reduced 35 ft in length and the top lowered from elev 213 to 210.

24. Flmv conditions within the stilling basin of recommended

design v-rere excellent for both twin- and single-conduit operation (photo-

graphs 12-14). ·Hater-surface profiles showing the location of the ·

hydraulic jump in each half of the stilling basin for the most important

discharges are shown on plate 10. Results of erosion tests for the same

discharges are shown in photographs 15 and 16. Comparison of these

scour data with those obtained downstream from the stilling basin of

original design (photographs 3 and 4) indicates considerable improve-

ment. Velocity data measured over the cross section of the channel at

the end sill are shown on plates 11 and 12. These data indicate uniform

flow conditions across the channel. The maximum velocity recorded over

the end sill for both conduits in operation was less than 4 ft per sec

for all discharges. For conditions of one conduit operating (plate 11)

the maximum velocity over the end sill was 7.6 ft per sec for a discharge

of 14,000 cfs. The tailwater elevation could be lowered 15 ft for

16

discharges of 10,000 and 18,000 cfs before spray action occurred (plate

13); at the maximum discharge of 28,000 cfs the tailwater could be

lowered 10 ft before spray occurred. variation in tailwater revealed

that minimum end-sill velocities occurred at normal tailwater depth for

a discharge of 10,000 cfs (plate 14). Minimum velocity occurred at a

tailwater depth about 6 ft below normal for a discharge of 18,000 cfs.

17

PART IV: CONCLUSIONS A11]) RECOMMENDATIONS

25. Model investigations permitted the development of a satisfac-

tory design for all conditions of discharge and conduit operation. The

most important aspect of the problem of securing good flow distribution

in each half of the stilling basin was the development of a transition

at the conduit exit portals. This transition involved the supereleva-

tion of the floor 5 ft to divert flow away from the splitter wall. It

was necessary to increase the over-all length of the stilling basin 50

ft, inasmuch as it was desired to place the transition entirely outside

the conduits rather than make it a part of the exit portal. The increase

in length of the stilling basin was accomplished by shortening the con-

duits. Details of the stilling basin design recommended for construe-

' tion in the prototype are shown on plate 9.

26. Flow conditions with the recommended stilling basin design

were excellent for all conditions of discharge and conduit operation.

Also a considerable reduction in tailwater, belo>v that computed, could

occur without decreasing the effectiveness of the stilling basin.

PHOTOGRAPHS

Discharge, 5,000 cfs; pool elev, 259-50; tailwater elev, 203.95

Discharge, 10,000 cfs; pool elev, 259-50; tailwater elev, 210. 00

Photograph 1. Flow in original design stilling basin was downstream in direction along splitter wall and upstream along spray walls

at low discharges



Photograph 2. Flow in original design stilling basin remained downstream in direction along splitter wall and upstream along spray walls

at high discharges



Photograph 3. Scour in exit channel caused by low discharges through original design stilling basin

Discharge, 18,000 cfs; pool elev, 259.50; tailwater elev, 213.10


Photograph .4. Scour in exit channel caused by high discharges through orjginal design stilling basin

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Photograph 5· Scour in exit channel caused by low discharges through original design stilling basin with

baffle piers removed


Discharge, 18,000 cfs; pool elev, ~59-50; tailwater elev, 213.10

Photograph 6. Flow conditions with basin width at end sill decreased by 44.5 ft


Discharge, 18,000 cfs; pool elev, 259 . 50; tailvater elev, 213.10

Photograph 7. Flow conditions with broad-crested weirs installed in stilling basin



Photograph 8. Flow conditions with wedge- shaped fillet placed adjacent to splitter wall



Photograph 9. Scour caused by flow with wedge- shaped fillets adjacent to splitter wall

.,



Photograph 10. Flow conditions with superelevation of basin floor and increased radius of curvature of spray walls


Photograph 11. Splitter wall r emoved

Discharge, 5,000 cfs; pool elev, 259-50; tailwa~er elev, 203 . 95

Photograph 12. Recommended stilling basin design

Discharge, 10,000 cfs; pool elev, 259.50; tailwater elev, 210.00 Twin conduit operation

Discharge, 14,000 cfs; pool elev, 259.50; tailwater elev, 212.30 Single conduit operation

Photograph 13. Flow conditions in recommended design stilling basin with single and twin conduit operation


Discharge, 28,000 cfs; pool elev, 259- 50; tailwater elev, 214.70

Photograph 14. Flow conditions in recommended design stilling basin for high discharges

Discharge, 10,000 cfs; pool elev, 259.50; tailwater elev, 210.00 Twin conduit operation

Discharge, 14,000 cfs; pool elev, 259. 50; tailwater elev, 212.30 Single conduit operation

Photograph 15. Scour caused by discharge through recommended design stilling basin

Discharge, 18,000 cfs; pool elev, 259-50; tailvater elev, 213.10

Discharge, 28,000 cfs; pool elev, 259-50; tailvater elev, 214. 70

Photograph 16. Scour caused by discharge through recommended design stilling basin

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DISTANCE IN F'EET FROM CENTERLINE OF 8 ASIN

60 40 20 ~ 20 I I I I

S.2J [;J.g, 11.4$ '..!MP 1'11 M J46° m· .. -!.d£ ..... L!.! Z!.l ~ 170° J$2 • Jss• .. ,. 4. ZS 4. 25 4.90 4. f0 S ./0 11s• 175 ° .1$1'. D- 7 4. (0 . 4.20 4.60 4.40 4.40 7iU' 17

,., .. ••

NOTE : F I GURE A BOVE LIN £ IS VEl-OCIT Y IN P ROTOTYPE

F EET PER SECON D .

F ICURE &El..OW l-I N E INDfCAT ES AN CL E OF f l-OW

MEASUR~O O..OCKWlSE FROM DOWNSTREAM DIRECTION.

40 6 0

R I GHT $PRAY WAL L

210 ... "' TEST CONDITIONS

6 ./ .J :!

S.IO .... zoe w w D ISCHA RGE ~Jooo c rs 200 if POOL E L.:EVATIO N Z$~.$0

~ t-!.£ ;;; TAILWATER ELEVI<Tt ON 203.96 16° 16. z

190 0 TWO GONOVITS o 'PERATING

4.~$ ~ ~ 10. ,.. >

~ 3. 1$ 3 .$0 "' r lr 180

40 60 I I

RIGHT SPRAY WALL

2 10 .J TEST CONDITIONS .,

7. / J ~ ::. .... lo• 19 0° 200 ... O ISCH AA.G£ 10 .,000 as if POOL eLEVATION 2.~9.,0

!!.£. 4. 90 ;;; TAILWATER ELE VATION 2 10.00 6 . 7iOo z TWO CONOUtTS OPERATING

190 0

~ .t.zo ~ 18.$0 tgs• >

4. 25 iW it§.. 1&0

~

VELOCITIES AT END SILL ORIGINA L DESIGN 5,000 CFS - 10,000 CFS

DISTA~E !!>& F'EET FAOM C £NTE:RLINE OF &ASIN

60 40 20 .... 20 •o 60

\.EFT SP1tAY W ~ RIGHT SPRJ.Y W._l.\.

l!O .... ~ ~~ I~ ~ (!J_?.§ 5.10 2 10

.,; iW J4()"' J 48° o• u• zo• , ... ... TEST CONDITIONS

3 ~ ~ rUJ ~ w 5.ZS

i t:; ~ ~

OISC ).OARGE IS1 0 00 (; I"S

zoo 161'0 J<ll" .. c• .. ,.. fiiO zoo w PCOI.. ELEVATION 2.~9.~0 ~ "' ... TAILWA'TER ELEVATION 2 t 2 .4S ~ ug '·"' ~ !l:.tJ ~. 40 4110 !&.q ; z 168° 3$J• o• o• .. 700 I!JO• z TWO CON OV!TS OPERATING

Q l•c 1 •• 0

~ !,;.!1 ::/;'. 6 . 4() /2.00 ~./5 Ul 4.25

~ 161' 0 o• o• o• 187• ''"'" ~ 4.10 4.1$ 4.2$ $ ,25 U§. Ul <.2$

18¢ i61' 1'1!' o• o• o• 187• liFo 1&0

DISTANCE IN f EH FFI.OM C ENTEfiti.. INE OF 6A$lN

60 4 0 20 ¢. 20 4() 60

LEFT ~PRAY WALL JU~T $1'AAY W"\.1.

a lo 1,4 () 9.1/J t..1.70 11.10 /J./J g, l/6 7.40 210

;;( JJ6• 348° -.. 7 ... 7T" zr• ~

TEST CONDITIONS

~ 6 . 40 ~ 11.5$ ~ I.I.J.9 ~ ... > O!$GMA!\O! 1&,000 GF~ t; zoo li7o 34 f 0 0. o• o• , .. iW 200 ~ PCOL ELEVATION Z~9.~0

lr ~ .... 4 , .f() g,45 " zs 'OJO "'" ' .. TA!LWATER ELEVATION 2 t3 .10

2 16 1• m· ..... .. .. 187• iii"• • TWO CONCVITS OP ERATi l'I.'G

0 190 0

s :6~~ :;~ 1 .40 ~ U!1 1JP . £D

~ ~ ..- o• o• 1:67• 194 .

; "' UQ il/2 ~ UJl J.,.?j ~ 180 ,., ,.. o• .. .. 181• f$.t• 160

CIS TANCE JN FEET FROM CENT!Rt.!NE OF 8ASIN

6C 4 0 20 <k 20 40 60

LEFT SPRAY WA L AICW'l S PA" V WA\.1.

l!O / 4, J$ 16.10 1~. 9{) 14 . .J$ 16.$<) 16 .40 f.4.JS <1 0 TEST CONDITIONS J 4&• JS.J• o- o- .. -;: 7i"i J

~ 'S , 14.6 6 OISCHAA.GE u.ooo crs

~ ~ !1.li I.Ld2 ~ 117$ IJl:.AP ~

~ tO·O 141~ JH• .. o• .. .,.

~~~· 200 w POOl. i t.. iVATION 2.~~.~ ... TAILWATi.A EL (VATION 2 141 ,70

~ t$1 10 .11!. '!)&> '~ §.:.!..9 ~ ~

• 167 • 1 74° o• .. o• 187~ /94• • TWO CONDUITS OP£RAT!f'"'CO

2 ... ,., 0

~ .. ~ ~ 8.00 w w 4 .1(; 16 ,25

~ 1:, m· 174° .. o• o• ,~.,.

;;: ~ <-M £M Uf) ~ £1fl J, fj

'1) 160 16 7° /14° o• o• o• 187" 114• 1&0

r VELOCITIES AT END SILL )> NOTE F'IGVAE A80V£ L tN£ IS VfL(lC.I TY IN P ROTOTYPe_

-! F£E't ~EFt S£CONb ORIGINAL DESIGN JTI F'tOUR~ &ti..OW L INE INO!CATES .. NCLt OF F'LOW

M(A$VRf0 <:.t.OC:.I<W!$( fR OM 00WN$TR( A"' I>IR.E<:T!ON IS,OOO CFS, 18,000 CFS AND 28,00 0 CFS

w

0 1$ TANC£ IN FEET II ROM CENTE.R&.INE OF 8 A$ 1N

60 40 20 <t. 20 40 60

LEFT S P RAY WALL R IGHT SPRAY WA~L

215 2 15 J J TEST CONDITIONS "' ..

l :1 ... 7,$C 1(.15 16.10 11. 1$ 16.00 10.7!1 8.60

!; .. nr· JiO• $$()• 00 JO• 18° ~ DISCHARGE iO~OOO C F$ ::' 205 205 ~ POOL ELEVATION 259.50 ! :6:: 7. 40 1/.1$ IO.OC II. I() T.Z$ ~ ;!; TAILWATER ELEVATION 2 10 .00 z .1<~8• To Do To"" IF ~~~· z 0 195 195 2 TWO CONDUIT$ OPtRATING

~ ~ ytg 'c~" ~~() 8.>0 $,()() 5.00 s i:; IG7• .JJO• To"" JO• ii'7i w J

U.§ 5.00 ~ ~!0 !.:.ll !J9 ... .. ~· ..

185 167• u • o• o• 187• 94° 185

BASIN FLOOR AND END SILL RAISED 5 FT

DISTANCE IN FEEY FROM c fNl ERI-INE OF BASIN

60 40 20 <t. 20 40 60

LEFT SPRAY WALL RIGHT SPRAY WALL

220 220

.: ... TEST CONDITIONS l ~ ... t;; DISCHARGE 101000 CF'S .. 210 2 10 ~ ~ POOL ELEVATION Z$t. ,O

~ £.1.§ g,$0 ~ 11.10 16.00 9 .8$ 4.2$ ;!; TAILWATER ELEVATION 2 10 .00 172• 348° J$$• Do To ,.. j"j"iO

z ~ TWO CONOUITS OPERATING 2 00 200 0

~ 4 .$0 5 .00 /J.JJ 10.()0 1.3.65 $.00 4.ZJ ~ > 172° W • .1$$• 00 To IF ;no

i:; .. J

~ ./.25 10.00 9 • ./5 ~ £U 5.00 cl .. 190 112• J47• cs;• o• .. u• 181• 190

BASIN FL OOR RAISED 5FT END SILL RAISED lOFT

NOTE : F ICURE ABOVE LINE IS VELOCITY IN PROTOTYPE

FEET PER SECOND .

FICVRE 8ELOW LIN£ IN DICATES ANGLE OF FLOW EFFECT OF STILLING BASIN AND MEASURED CLOCKWISE FROM I>OWNSTREAM DIRECTION.

END SILL ELEVATION ON VELOCITIES AT END SILL

'1)

r ~ I'll

(11

LEFT PftAY WALL

210 -' .. ~

:;; 200 i:'

<! z Q 190 ~ > "' -' "' 1ao

Ot $ TANCE 1N FEET F ROM CENTERl.JN &: OF BASIN

6() 40 zo <t. ·zo 40

6.75 .J.Jo•

!I.ZS l§.d.g I£:!P lMl II.JS .Jto• o• o• o• w

S.2S 77o-

!£d.} 14. ,15 I!:!J /.#..1$ ~ 3to• o- o• o- •••

s.zs ITO•

8.50 10.6$ 11.65 10.65 8.50 280° o- o- o- so•

J.7$ J7o•

r.oo 7.~$ 7.00 r.oo ~ liS• .,... .,... .,...

1~5·

5.25 110•

~ • . $0 T.$0 4 .ZS gj ,. .. o• o• o• Z/0°

STEPS FLARED AT ANGLE OF 120 DEGREES TO SPRAY WALLS

NOT£ : F ICURE ABOVE LINE IS VELOCITY IN PROtOT YPE

FEET PER SECONO.

FICUR£ BELOW LINE lNOIC.,1ES ANGLE OF FLOW

MEASURED CLOCKWtSE FROM DOWNSTREAM DIRECTION,

6()

5 .75 w s.J.I liO•

•.go iio.

5 . 75 ~

S.JS 90•

R IGHT SPRAY WALL

210 _, " TEST CONDITIONS ~ .... "' OI SCHAACE 10 1 0 00 CF'S 200 "' ... POOL ELEVATION 2St.$0 ;::

TAILWATER ELEVATION 210 .00 z

19 0 0

~ TWO CONDUIT$ OP£AATI~G

"' _, "' 180

EFFECT OF FLARE OF STEPS ON VELOCITIES AT END SILL

DISTANCE IN FEET FROM CENTERLINE Of= BASfN

40 20 <t. zo 40

EFT SPRAY WAL RtGHT SPRAY WALL

··~ ~ ~0 !Y!2 u .so ~:~ 210 ... o• .11Q• o• ..,.. ...

TEST CONDITIONS "' "' :f U}. '~!o 8.$() lll.J 8.$() :f

::; 200 o• o- o• o- ::; OISCHARGE 10 10 0 0 CF$ ... zoo

~ ... POOL El..EVAT ION 2~9.50

;; $,()Q 6.2$ s.co ~ #,75 ;; TAILWAT ER EL EVATION .

210.00 .. Oo Oo o• o• z

19t

z TWO CONDUITS OP[RATING 2 190 ~ 1- .1.60 ~ 7. 1$ 4 .1j ~ ~ .. o• F o- o•

~ ... ... 3.2J J.60 T.TJ 3.~0 3.90 ...

teo- :or. o• o• o• o• 180

DISTANCE IN FEe T FltOM C !NTitJ\t..INE OF &ASIN

40 20 <t. 20 40

L EF'T SPRAY WALL RIGHT SPRAY WALL

210 10.74 /Z.50 11.50 120~0 10.74 210 ... o- 00 Oo o• ... TEST CONDITIONS "' "' :::; /().~$ 1.1&2 /#,()()

::1 I~ I~ .. ::;

200 .. o• o• Oo o• 200 "' 0 1$CHAA.GE t8 1 000 CFS

~ ~ POOL EL EVATION 2~9.50

;!; 7.5Q /2.$() 1/ • .ilO J.1 .$0 T.$0 ;; TAII..WATt R ELEVAT ION 2 13.10 ... Oo ... o- o-z z TWO CONDUIT S OPERATINC 2 190 190 2 ,_ I . T$ IJ,;Z4. 12.50 11.14 6.7$ ,_ ~ o- o• .. .. .. ~ ... ... ...

4.7$ 1/.74 11.7# /1.$0 4 . '!$ ... ... ...

ISO o• o• o• o• o• 180

NOTE : F'I GUR.£ AeOv£ \.IN£ IS VE LOCIT Y IN PROTOTYPE

F££T PER SECOND.

F I GURE 6ELOw L-I NE INOtCATE.S ANc:;. t,.E OF FLOW EFFECT OF REDUCTION IN M EASURED Ct..OC~WtSE FROM OOWNSTREAM DIRECTION.

WIDTH OF STILLING BASIN ON VELOCITIES AT END SILL

01STANCE I N FfET FROM CEN TERl.INE OF BASIN

60 M) 20 ~ 20 40 60

l E.Fi SPRAY WALL A IGI'f'T SPRAY WALL

21> 215 ..J ..J

TEST CONDIT IONS ., ; :! ... 8 .75 10.51) 1£:!.9 1£&..5 @d5! 10.00 !:11 ~ w .,.,,. J.Jr• o• o• o• z;; u• OISCH ARGE 10 1000 C: FS if 20> 20~ w ... POO\.. ELEVATlOt.$ 2.~9.~0 ~ $.35 ~ ~ !:lP 8.15 r.so S.J5 1!' TAILWAT £A: El EVATION 2 10.00 z J 40° Jt1Z• o• o• 00 18 ° zo• z 0 ••• • •• 2 TWO CON DUITS OPERATING

~ 3. TO S .Z$ 6.0 0 7.00 6.()0 ~ 4 .ZO .. > J4l 0 J 40 ° 00 .,. 00 zo• 18° > "' w ;:l 4 .3$ ti. ZO 4 . .35 $.()0 4 .60 ~ • .JS !.:.§£

..J w ••• W• J44° o• o• 00 fl. !8• •••

DEFL ECTOR BLOCKS - TYPE c

OISTANCE IN FEEl' f'ROM CENTEFU .. ,N E OF & ASI N

so 40 20 ~ 20 40 &0 I I I I I I

LEFT _5_PRAY WAL L R IGHT SPRAY WAI_L

2 15 2 1> ..J _,

TEST CONDIT IONS ., ., s

~ !:£f' II. S O 9.00 11.15 9.00 8.J5 s ... ... "' 20S

J47° JSJ• 00 o-- ·oo 7- f# O 20> i:l DISCHARGE K>,OOO CFS

It ... POOL EL£ VA.it0N 25.9 .!10

"' 7.Z$ 1.J$ 1 .00

' r.oo 7.15 ~ !:.il ~ TAILWATER ELEVATION 2 10.00

" W • J5JO 00 o- 00" 7• ,..

z TWO CONDUITS OPERATING 0 ••• 19~ 0

~ •. oo 4.60 !:ll.. 4.15 4.50 <1.75 6.00 ~ J~T • J$J• o• 00 o- -;-. 7;0

~ ;;; !d1 3 .Z5 3 . .2.5 J.6o 3.50 J . SO 4 ,00 ~ ISS J47° JSJO o• o• o• 7 • ,,. •••

DEFLECTOR BL OCKS - TYPE D

N OTE : F IGURE A BOVE l,.IN E" 1$ VE L.OCIT Y IN PROTOTYPE

FEET PER SECONO.

FIGVRE SEI..OW ~INE IN O, CATES A NC.t. E Of F\.,OW EFFECT OF DEFLECTOR BLOCKS AT MEASUREO CLOCKWISE FROM DOWNSTREAM DIRECTION.

CONDUIT EXIT PORTALS ON VELOCITIES AT END SILL

LEFT S PRAY WALL

2 10

;;( ~ ,_ "' 200 1:' !!

~ ~

1!10

~ ... 1<0

01$TAN:C! IN F££T ,RON CI!NT£·RL IN!. OF BASIN

eo 20 <k. 20 40

10. 2$ J47•

/().00 10.00 8.65 m· o- o-

~ J~T•

8.2$ !dl !:!e. ~$1• o• o•

J.TS JiC•

5. 4 0 4 .15 5 .$0 To o- ....,..

4./!J 3$0•

3 . 76 .J.75 4 .$0 JSO• o- ..

Lj{' ... J.SO .].25 .3.75 Jso• J40• o•

NOTE . f'ICUA.E A&OVE LJNE tS V!:t.OCIT Y IN PROTOTYPE

FEET PER SECOND.

FIGURE BELOW L INE INDICATES ANGLE OF FLOW

~EASUREO CLOCKWISE. F ROM DOWNSTREAM 0 1R£CnON.

/0.00 10.00 o- -,.-Ul 6.Z$ o• To

4 ,7$ $.40 Oo 00

~ .3.7$ o• JO•

3.25 3.50 zo• JO•

eo

AICHT SPRA'r WA.I..I..

10.25 2 10 7P ..1 TEST CONDITIONS .. 4.25 l -;;;- ,_

DISCH.O.RG€ 101000 CFS zoo ...

1:' POOL ELEVATION a~e.$0

5 .75 !! TAll-WATER EL£VATION ZIO,OO 7F z TWO CONDVITS OPERATtNG

190 0 4.2$ ~ JO•

~ .1.75 ..1 ... !$• 1&0

EFFECT OF WEDGE - SHAPED FILLET AT CONDUIT EXIT PORTALS ON

VELOCITIES AT END SILL

1J r ~ fT1

0

_J <f)

::;: f-UJ w lL

~

z 0

~ > w _J w

230

220

210 f-

200

190

180

170

160

ISO 0

I I I L I I

I I """-. k

~SPRAY WALL WITER-SURFACE PROFILE- DISCHARGE 18,000 CFS~ (TAILWATER ELEV 213.1) I ----~--- ----< r-

1"--.. ...... -- -----f.--r-----..... r-......,..-~ -- ' ·-- r-- ·-_ .......

~ ............... ~

40 80

NOTE: POOL ELEVATION= 259.5

I .! SPLITTER WALl - .L -- -- --r-- -- -- -- --r-.. .-----~---

r--~ ~I\.

~ '-----WATER- SURFACE PROFILE-DISCHARGE 10,000 CFS

(TAILWATER ELEV 210.0)

""', "'"' \ fl r

120 160 200

DISTANCE IN FEET ALONG CENTERLINE

I

240 280

WATER- SURFACE PROFILE RECOMMENDED DESIGN

OIST-.HC.~ $N P'!t!T fROM <::E.NTef\LINI! <# 8A$1N

60 .. 20 ~ 20 ~ 60

E.f'T SPfit.AY WA ' R IC.HT $PRAY WAI..\..

"l 410

~ TEST CONDITIONS

;; " • .Jo~' J21 ,

OISCMA.AG€ $ ; 000 CFS

E ~~:.

~.1$ ';// ~,~ 6 , 1$

· ~ zoo .... 00 , ..

20 0 POOL lil..liVATION 2 5-<J.$ 0

TAILWATEA £LE.VATION ~oa.o$ ~ ~ l.lJ Jo~s 1 .1$ ';;~$ 3:/.~ ~.cs ~

:ur• .JSJ• .. ,.. z TWO CONDUITS OPtRATtN<:i

~ 190 190 0

~ J.PS !..:lJ /,T$ l.dl 1 .1$ Z .15 ~·}: ~ W"· 3s.r .. .. .. 77

~ I w. 1.0() !~ ~ I.OC 1.00 P.15 I&OL ~,,. 'JSJ• .. .. .. T• ,.. •••

OIS TANCE I N FEET ~AOM CENTEAI..INE OF 8A$1N

"' "" 20 ~ .. •o ISO

I..EI'T ~AA't' WALL AICI-(t" S PRAY WALL

2 10 ~::. ,... .... 8.11',) 6 .60 1.10 1.60 ••• TEST CONDIT IONS

.J ;m-. .... .. .... .......- 'W" .J

~ 1.00 6.1$

~

i so!o ~? s0~o .!d:! 1.00 ~

OISCHARGE 1o .. ooo CF"S

200 J.t1• J$3* ,. --;:;-;- u POOL IELEVATION aso.~o 200 ~

~ TAILWATEA £L(VATION 110 .00 i ill !:n ~.IS .t.1S .t.ZS 4.ZS .t.lS ~ z .J.t1• Js.t• .. .. 00 ,. ,..

z T WO CONDUIT S Oi"£1tATING

~ 190 19 0

0

;::. ~~s. Z.TS ~.zs l . U l.ll ~~~5 ~ .. .. .. ,. ;4~~ 2 .75 l.1S l.1S z.tS Z.TS 3. 1$ w

180 ...,. .. o• .. ,. , .. 180

0 1$TANCe. IN f"I!I!!T t'A'OM G!NTfAI..INI! Of' 8 "SIN .., "" 20 <!;.

~· 4 0 ISO

j I I I j I I

,£n .P.AY WA A!CNT SP!tA'I' WALL

••• 1.1.1$ 1$.40 "";? 1!)/! ~~! oi.TS ~~~~ 2 10 ~

W• m· w .J TEST CONDITIONS ;

~4':. :i~~ /j. <IO S . .Jt> 3 .2$ /1.75 J . J$ ~

~ ~ Oi$C~AG€ ••.,ooo CF$

200 o• $• , .. To• 19S• 200 POOL £ L £V.tr.TION 2.S9.SO

T,i~ILWA.T'ER £~£VATI0N Z l3,)0 ! a!P JO.lS /J ,.$!) J.z.s 2.15 JJS J .U ! J #l • ,..,. .... ....... nr• zzo• lfJS• ONE CONOUIT OP! IItATING ~ 190 100 ~ ;: l'. O(J §.:.!.£ 9.~0 "'f! 4 .1'5 J.l$ ~ ~

~ .1#1• ,.,. o• 125° 'i20• 1/1$•

~ ~.1$ 6./S 1.60 .J .. 2S J.25 ~.25 J .JS 180 W• 35J 0 CF' ... m·----m· ,gs• 100

VELOCITIES AT END SILL NOT! ' FIQVI=tl! 480V€ L.-1"-- li !$VELOCITY IN PROTOTY~!

FtE'T P£R s£eowo. RECOMMENDED DESIGN FIGURE el!t..OW \. IN( INOICAT£$ ANGL £ OF FLOW ME~MD CU>CKW1SE FROM I>OWNSTA6AM 0 11\!CTiON. 5,000 CFS , 10,000 CFS AND 14,000 CFS

DIS TANCE \ N HET FRO~ CENTE.RLIN£ OF 9 A$!N

eo 40 20 <t. ZQ 4 Q •• I I I I I I I Ltfi S PAAY W 1..1. R IGK'r $PRAY WALL

. 10 8../.Q. §f:f.. - !N.l ILOJI ~ IJ..& e lo TEST CONDITIONS ~

.)47• o• o• .. ,.. .: > 7.6<1 !Jfl.. ~

, DISCHARGE .. !21/P ~ A.m. = ~

16,<)00 CF"S .. 200

J#"• .JS3• o• .. o• 7' , .. POOL ELEVATION 2bi. SO : 200 1'A!LWA1'ER ElEVATION 2 12 .45

~ ..a J..U DlJ1. UQ. li1J! ~ !,ll ~

' 347• 35J• o• o< .. ,. , .. z TWO CONCVITS OP ERAT ING

2 190 100 Q

~ ll,! .2.M Lff! ~ LiJ l.I§. 4 .21

~ > J47' JSJO o< o• ,. .,... ~

~ iff. Ll1. 1M l.U Ll1. ~ ::: 100 o• 0 o• 7• 100

OISTANC! IN F'U'l' F ROM CENTERLINE OF BASIN .. •• ~ <t. 2 0 40 60 I I I I I •

t.f:FT SPRAV WA Al<iHT $PRAY WA1.\.

2 10 ~·:~. 1/US 11# ¥. {}.41 '¥/ ~ 2 10 T EST CONDITIONS "

Jn> ,. " " ; ,

~. l.iJl &f.' 1J.fJJl ~ MR. Iff, O!SCMARG! t&.ooo c r s

g zoo ">" .. 7• 200 ~ POOL £ L£ VA.l"ION 2.$9 .~0

T.AILWATER ELEVATION Z.IS . IO ! ~. m. $ ,$() 850 550 us .,,

! ........ .... .... ...,... 74' TWO CONDUITS OP ERATING % % 2 l•o ... 0

~ Hf. !ii· ql. ¥- m 3.2$ ~ ~ > o• -r-~ jH. =- ~ = ~ 3.ZI. lf1. ;;:

100 ,.,. •.. , . 100

DISTANCE IN F'£ET !~='ROM CEN TERLINE OF B A.S!N .. 40 20 <t. 20 40 .. LEfT $PRAY WALL

Rl~\o1T S [II>I\AY W'AI..L

2 10 fiP, ~ 1~0! ~ = ~ ~ 2 10

" . .. 7 ' , .. .: TEST CONDITIONS

" , ~:. 1M! ¥. 1~./J.S "'"" '¥/1

, 0 1$CHARG£ .. II$ .. a:a.ooo CFS

J4?• o• ...... ...,. ~ 200 zoo "'

POOl. EL EVATION Z,.9.$0

! ... u o y ,, ... 'lf! .z.n ~ ~

TAILWATER ELEVATION 2 1-4.70

z .. ,. Jn> .... ,.

2 TWO CONOU!T$ OPEA.AT!NG

2 ... "'" 0

~ fij. 11!-. IIUS &SO 10~ us. ¥/. ~ ....... .,... ,... t #()• ;:; ;;! 2 "1-f w U1. ~ ;.p J2$ !fA ~

100 34.10 .. '""' 100

VELOCITIES AT END SILL NOl£ : F' IGURE ABOVE LINE IS VELOCIT Y IN PROTOTYPE

F££'1 PE R S£CONO . RECOMMENDED DESIGN FIQVRE O£LOW l,. INE INOIGATE$ ANGt.£ OF f LOW MI!:A$VAfl> CI.OCt<W!U F llOM ()OWNSTREAM OIR£CTION. 15,000 CFS, 18,000 CFS AND 28,000 C FS

"'U r )> -I rn

..J U)

::;; 1-w w "-

~ z 0

220

210

i= 200 :ff; w ..J w a: w 1-..: 3:: ..J

..: 1-

190

180

I

' '

I

0

I i

I I

I

i I

I/ i / ! I

;

' I I I

! -1----' F-

!

5

I I

' I

i I

I I ;

' I i ---r I I I ,_.....v i ' y

/f I

I /

I I

!

i I

I I I

' !

I

;...--- 1-1--- I

I

10

'

I I I

' I

I I _j._.J l--

I j_..-.--\. I I

!'--- ;ORMAL TA/LWATER

I

'

I I ! ! --I -1-F--

1-1-1-r\: - T i "-._ SPRAY CURVE

' I I

I I I

I

I

15 DISCHARGE IN 1000 CFS

20

I

I i

I

1--f.--

I

I

'

I I I I

I

./ I v

/

v f-' I

25

220

210

..J U)

:::;;

1-w w "-

~ z 0

200 1-:ff;

I

I 30

90

80

w ..J w a: w 1-..: 3:: ..J

..: 1-

TAILWATER CURVES

..J U)

::i: I fw w u.. z z 0

220

215

210

~ 205 > w ..J w a: w ~ ~ ~

200

195

190 2

PLATE 14

v v )

lc1 v / /

()Cj ''j' / I/

~'? 1/

~ v ~I

c; ~"/ ,p ~'? 1/' NORMAL TAILWATER £LEV.

~?/ Ci/ ooo cf/1 rP/ ,I'J.

I "'~'MAL 7i41LWAT£R {o9 if J 1.---- £LEV. rJ'

1/ I I

I/ v \ L v I l /

,\ 1\ I

i\ r..-- .l

t 1\1\ I\

'\

I\ \ " ", " " \ \ ', 1\.

\ ', ['.;: " ~-

\ "· ' '· \

1'--. ', r,

1\ "· "· 1\ I" h 1'\

3 4 5 6 7 8 9 10 VELOCITY IN FEET PER SECOND

LEGEND

-- ORIGINAL DESIGN --- RECOMMENDED DESIGN

NOTE: VELOCITIES MEASURED ONE FOOT ABOVE END SILL.

TAILWATER VS VELOCITY CURVES

OUTLET WORKS STILLING BASIN FOR TEXARKANA DAM …hydraulic-jump type stilling basin. Design capacity...

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