Special Report

Precast Prestressed Concrete IBridge Deck Panels

Prepared by

PCI Committee on Bridges

DONALD GOLDBERGChairman

THADDEUS D. ASHWILLALEX AS WADJAMES M. BARKER

ROBERT M. BARNOFFKRIS G. BASSIELIAS BEHAR-YBARRANED H. BURNSJESS COLLIER

JAMES H. GATESWILLIS G. GRINSTEAD

JAMES S. GUARREPETER HAVEN, IIWAYNE HENNEBERGERRICHARD R. IMPERJAMES K. IVERSON*STEVE R. JOHNSON

HEINZ P. KORETZKYJOSEPH P. LOBUONOROBERT J. LOEHR*CLELLON L. LOVEALLRICHARD M. MCCLURE"MARK MOOREGORDON NAGLECLAUDE NAPIERJOHN P. PETRASEKH. KENT PRESTONBASILE G. RABBAT*CHARLES E. REJCHAKENNETH J. SAN DERSONMAYNARD C. SCHENKMARIO G. SUAREZDAVID VAN HORNHOMER M. WALKER'

*Members of Deck Panels Subcommittee, Homer M. Walker, Chairman.

26

The purpose of this report is to present guidelines forthe design, manufacture and erection of precastprestressed concrete bridge deck panels. Theseguidelines are based on the latest research andpractical experience gained from their use in variousparts of the United States.

After a brief review of the history of bridge deckpanels, suggestions are given for the dimensioningand detailing of panels, techniques for castingpanels and helpful ideas in the handling, shippingand erection of panels.

An Appendix section provides a fully worked designexample of a bridge deck panel meeting AASHTOSpecifications. In addition, a large variety of bridgedeck panel applications in pictorial form are included.

CONTENTS1. introduction ...................................... 28

2. History ........................................... 29

3. Details ........................................... 29

4. Casting Panels .................................... 30

5. Erection .. ........................................ 32

6. Conclusion ....................................... 32

References ......................................... 33

Appendix A Bridge Deck Panel Design ............... 34

Appe n d ixB Applications ........................... 38

PCi JOURNAUMarch-April 1987 27

1. INTRODUCTION

P recast prestressed concrete deckpanels are widely used in the con-struction of bridges in the United States.A 1982 survey of the State Highway De-partments by the PCI Bridge Committeeshowed that 21 states use the panelsregularly and another seven states weretrying the method through bidding op-tions or were developing details prior totrial projects.

The panels are used as a compositepart of the completed deck. They re-place the main bottom (positive mo-ment) transverse deck reinforcementand also serve as a form surface for thecast-in-place concrete upper layer thatcontains the top of deck (negative mo-ment) reinforcement. A typical deck

panel detail taken from the Illinois DOTdesign standards is shown in Fig. 1.

The use of precast panels has provento be both economical and convenient.'Generally, when a deck is cast in placefor its full depth, timber forms must beinstalled and later removed. This is ex-pensive, time consuming and in manylocations causes safety concerns toroadway traffic or pedestrians under theconstruction. On high level crossings,placing and removing deck slab forms isa safety concern to the workers.

The purpose of this report is to pre-sent guidelines for the design, manu-facture, handling, shipping and erectionof precast prestressed concrete bridgedeck panels. In addition, a fully workeddesign of a bridge deck panel meetingAASHTO Specifications is provided in

YSLEI MSfE;3/4"C $TVOS 1 1

L 1/2 [j I I/2" I rit6SEl0VER PIERS^214"CL

SLAB DEPTH

ri5 E4- SPA BETWEEN BEAMS I/^ PRECAST PRESTR

4"MIN lal I/2' 12 DECK PANELS

I+--i f/4 3 ICEMENT GROUT

f:FLANGE WIDTH PANELDESIGN SPAN' I

SLAB"DESIGN S PAN"

SECTION THRU SLAB

IS, 6-W5.SIW5.5W W_F SLIFT4NG HOOKS

^^,^ TYP v C.1/B"STRANDS

PANEL"DESIGN SPAN "+3"I ^^

io4-E0. SPA. AT 5"MULTIPLE!

RAKE FINISH TOP

N=NUMBER OF3/g'

I

270 KS i STRANDSPLACE STRANDSSYMM. ABOUT ft.PANEL-

Fig. 1. Precast prestressed deck panel details.

28

Fig. 2. Welded steel plate girder stream crossing in eastern Kentucky used the detailshown below. The steel frames are fabricated on site after determining the height fromtop of flange (bottom of 2 in. bar) to bottom of deck (top of angle).

PANEL

L3x2.3/16

PPC DECK PANELSARE TO BE GRADED BYADJUSTING THE HEIGHTOF THE ANGLE ABOVETHE TOP OF GIRDER.

PANEL

L3x2x YI6

I/4" 2" (3'- Q" C C )

the Appendix. Included also are a largevariety of applications of deck panels inpictorial form. First, however, a briefhistorical review of bridge deck panelsis given.

2. HISTORYPanels were first used in the nineteen

fifties and a 1956 project on the IllinoisTollway is often cited as an early exam-ple. A number of states began to use the

panels in the late sixties and earlyseventies. Several research projectswere undertaken at that time. The re-search results were positive and currentdesign is based on this work and theearlier designs that have functionedwell.

The earliest installations of the deckpanels are nearing 30 years of age andthe decks continue to perform well.2Some bridge decks using panels haveexperienced reflective cracking in thebridge deck surface, directly above the

PCI JOURNAL March-April 19137 29

butt joints between the prestressedpanels..' These cracks normally termi-nate approximately halfway through thecast-in-place concrete slab, and have notbeen found to have any significant effecton the performance of the structure.

In fact, the cracking is often less se-vere than that found in carefully sur-veyed fully cast-in-place decks. Crack-ing problems related to nonrigid hearingof the panels on the longitudinal beamswhen positive bearing is not providedare a serious concern and the structuralintegrity of the slabs has been ques-tioned. This type of cracking has notbeen a problem in panels properly de-tailed with a grout or concrete bearingon the flange of the supporting beam.

3. DETAILSA crucial aspect of the performance of

panels has proven to be their detailing,especially member dimensioning, typeof reinforcement and joint details. Thetransverse positive moment reinforce-ment in the deck is provided by preten-sioning strands at mid-depth of thepanels. Questions of strand develop-ment in the shorter panel lengths, ap-propriate design procedures and evalu-ation of wheel load distribution acrossthe open transverse panel joints wereanswered positively in the early re-search. s I

This research also indicated that chlo-ride penetration (through the topping tothe panel) did not occur. Corrosion pro-tection of the strand is provided by thehigh quality concrete used in the panels.

Panel dimensions have varied, butpractical ranges have been found to he:

Thickness: 2'/2 to 4'/2 in.Width: 4 ft or 8 ftLength: To provide a minimum of 3

in. of hearing on the beam flanges.Some designers believe that the min-

imum thickness of panels should he 3'in. in order to be in conformance withAASHTO Section 9.25.1.1 which re-

quires 1 1/2 in. clear cover. (The 2% in.panel is based on 1 in. cover as stated inSection 9.25.1.2.2.) Also, the 3 in.thickness would reduce the possibilityof cracking in the panels due to handlingand the longitudinal splitting at strandsnear panel edges.

The early panel projects used a detailwith the end of strand extended outsidethe panel for 4 to 6 in. Research hasshown that this extension is not re-quired. 9 In the transverse joints, buttends have proven to be a straightforwardand durable solution to adequatelytransfer the wheel loads.

Research has also demonstrated thatmechanical shear ties on the top of thepanels are not required. Care in rough-ening during fabrication and providing aclean surface prior to placing the topcourse of concrete is necessary.

Recent reports on deck cracking andgood experience with other decks havedemonstrated that the panels must befirmly bedded on grout or concrete onthe longitudinal beams. A number ofsatisfactory details have been used thatprovide elevation adjustment betweenthe top of the Iongitudinal beam and thepanel and also provide grout space.Three of these are shown in Figs. 2, 3,and 4.

The strands in the panels are gener-ally % in. diameter, but 7/ie and I/z in.strands have been used in several states.Caution is advised when using strandslarger than /16 in. The strands should becentered in the depth of the panel andbe spaced uniformly across the width.This will help prevent vertical bowingof the panel prior to placing in thestructure. Most highway design groupshave developed their own details andspecifications. Many bid the cast-in-place deck and allow the contractor touse the panel system, based on standarddrawings, as an alternate. The IllinoisDOT standard (Fig. 1) is fairly typicalalthough a number of details are han-dled differently from state to state.IDOT uses a variable depth grout bed.

30

M+ '

iifit^le

Fig. 3. This view of the Colfax Bridge over the Saint Joseph River in South Bend, Indianashows the diaphragms cast in place. The panels are stored on the beams to speed thefinal placement. These panels were placed on a fibrous material. An effective detail,shown below, is being used in a number of states, with good results.

O HIGH-DENSITY EXPANDED POLYSTYRENE FOAM rt BEAMBEDDING MATERIAL AND SHALL CONFORM TO I I'THE FOLLOWING SPECS. :COMPRESSION STRENGTH60 PSI MIN.,WATER ABSORPTION 0.125#FT2MAX. AND OXYGEN INDEX 24 MIN. AND SHALL j I '.: a " ' '''BE IN ACCORDANCE WITH ASTM D-1621 N .' (MIL-P-19644c). 2 (21.X- = L

O GROUT TO BE PLACED PRIOR TO PLACEMENTOF PANELS. . 21 I Iz

PANEL SUPPORT DETAIL

Welded wire fabric is used for longitu-dinal distribution steel and can alsoserve as lifting loops.

The reinforcement in the panels,placed perpendicular to the prestressingstrands, is required for load transfer andstrand development. Typical details areshown in Fig. 1 and are specified inAASHTO Section 9.23.2. The cast-in-place top course contains transversenegative steel over the longitudinal

beams and longitudinal steel should beprovided in accordance with AASHTOSection 9.18.2.2.

4. CASTING PANELSPanels are cast on standard long line

beds. The panel's top surface is rough-ened to provide mechanical bondingwith the cast-in-place topping.

PCI JOURNALMarch -April 1987 31

The purpose of this report is to present guidelines forthe design, manufacture and erection of precastprestressed concrete bridge deck panels. Theseguidelines are based on the latest research andpractical experience gained from their use in variousparts of the United States.

After a brief review of the history of bridge deckpanels, suggestions are given for the dimensioningand detailing of panels, techniques for castingpanels and helpful ideas in the handling, shippingand erection of panels.

An Appendix section provides a fully worked designexample of a bridge deck panel meeting AASHTOSpecifications. In addition, a large variety of bridgedeck panel applications in pictorial form are included.

CONTENTS1. introduction ...................................... 28

2. History ........................................... 29

3. Details ........................................... 29

4. Casting Panels .................................... 30

5. Erection .. ........................................ 32

6. Conclusion ....................................... 32

References ......................................... 33

Appendix A Bridge Deck Panel Design ............... 34

Appe n d ixB Applications ........................... 38

6. CONCLUSIONUse of precast prestressed concrete

deck panels results in an economicaldeck system and fast deck construc-tion. Proper design and detailing areimportant, and, if properly executed,will result in high quality decks withgood durability.

In a continuing effort to improve theindustry's products, the Bridge Pro-ducers Committee of the PrestressedConcrete Institute has commissioned aconsulting engineer to compile researchdata, study current design and detailingpractices and investigate productionprocedures (including tolerances). Theend result will be a "RecommendedPractice for Bridge Deck Panels."

REFERENCES

1. Barker, James M., "Research, Applica-tion and Experience With Precast Pre-stressed Bridge Deck Panels," PCIJOURNAL, V. 20, No. 6, November-De-cember 1975, pp. 66-85.

2. Gustaferro, Armand, "Performance ofPrestressed Concrete on the IllinoisTollway After 25 Years of Service," PCIJOURNAL, V. 28, No. 1, January-Febru-ary 1983, pp. 50-67.

3. Jones, H. L., and Furr, H. L., "Study ofIn-Service Bridges Constructed WithPrestressed Panel Sub-Decks," TexasHighway Department, Research Project

2-5-10-145, July 1970.4. Fagundo, F. E., Tabatabal, H., Soong-

swang, K., Richardson, J. M., and Calls,E. C., "Precast Panel Composite BridgeDecks," Concrete International, V. 7,No. 5, May 1985, pp. 59-65.

5. Kluge, Ralph W., and Sawyer, Her-bert A., "Interacting Pretensioned Con-crete Form Panels for Bridge Decks,"University of Florida for the Florida De-partment of Transportation, ReportD610-635F, December 1974, PCIJOURNAL, V. 20, No. 3, May-June 1975,pp. 34-61.

6. "The Interaction of Prestressed Concretefrom Panels with Cast-in-Place Decks,"University of Florida for the Florida De-partment of Transportation, 1972.

7. Barnoff, Robert M., Ordorff, James A,, Jr.,Harbaugh, Robert B., Jr., and Rainey,Donald E., "Full Scale Test of a Pre-stressed Bridge with Precast DeckPlanks," PCI JOURNAL, V. 22, No. 5,September-October 1977, pp. 66-83.

8. "Summary Report on Investigation toDetermine Feasibility of Using In-Place,Precast Prestressed Form Panels forHighway Bridge Decks," Texas High-way Department, PCI JOURNAL, V. 20,No.3, May-June 1975, pp. 62-67.

9. Bieschke, L. A., and Klingner, R. E.,"The Effect of Transverse Strand Exten-sions on the Behavior of Precast Pre-stressed Panel Bridges," Center forTransportation Research-Report 303-1Ffor Texas Highway Department.

10. Biswas, Mrinmay, "Precast Bridge DeckDesign Systems," PCI JOURNAL, V. 31,No. 2, March-April 1986, pp. 40-94.

METRIC (SI)CONVERSION FACTORS

1 ft = 0.305 m1 in. = 25.4 mm1 psf = 4.882 kglm21 pcf = 16.02 kg/m'1 in.' = 645.2 mm' in. 3 = 16,387 mm3

1 in 4 = 416,231 mm1 lb-in. = 0.1130 N-rnI kip = 4448 N1 lb = 4,448 N1 psi = 0.006895 MPa1 ksi = 6.895 MPa

PCI JOURNAL//March-April 1987 33

APPENDIX A - BRIDGE DECK PANEL DESIGN

Design Conditions

9'4" C TO C

Design span:L =7.50+2(0.25/2)

= 7.75 ft for panel aloneL' = 7.50 ft for composite section

(AASHTO 3.24.1.2a)Reference: AASHTO Specifications forHighway Bridges, 1983.

Material PropertiesPrecast concrete:f, - 5000 psi; f,, = 4000 psiDeck concrete: f, = 4000 psi

Allowable Stresses (AASHTO)

AASHTO notation will be usedthroughout the design example.Loading: 35 psf future wearing surface;HS 20-44 truck; 50 psf working loadduring deck casting. These loads arein addition to the cast-in-place slabweight.

All concrete: 150 pcfStress-relieved strand: fs = 270,000 psiReinforcing bar: f, = 60,000 psi

Type of s tress Temporary stressesCompression 0.6f,1,= +2400 psiTension 3 [J= 100 psi

Tension

Strand at release = 0.7f= 189,000 psi

Section Properties

Final stresses0.4f , = +2000 psi3 ^^ f= 212 psi

(corrosive conditions)-6 \^fC - -424 psi

(normal ambient conditions)

b

SLAB

b = 12 in. (unit width)b' = (E g1E 3 ) x 12= (/ x 12= 10.73 in.

I - 12(3)x/12= 27 in.1

S", = Ile,= 2711.5

h = 3 in.h = 5 in.

= 18 in.sSb = I /eb

Panel: = 27/1.5I = hh x/12 = 18 in.3

34

Composite deck:^A y 2.Ay z Az2 I

Cast in place 53.7 5.5 295 1.61 139 112Precast 36.0 1.5 54 2.39 206 27Total 89.7 349 345 139

Composite:c = 1Aq/1A = 484 in. 4= 48410.89

= 349/89.7 S, = (I4,)( 51 y,4) = 543 in."

= 3.89 in. = (484/4.11)x 1.12 S8 = IclebIc= Az 2 +I = 132 in.- = 48413.89

= 345 + 139 S,p = I'Ic,,, 124 in.3

Moments and StressesDead load (panels) ft = MIS,M = 12 w L "18 = 2363/132

= 12 (37.5) (7.75) 2/8 = 18 psi= 3378 lb-in. fop = MIS r,,

frp = M/S t, 2363/543= 3378118 = 4 psi= 188 psi f,, = M/S,

fb = MIS, = 23631124

= 3378/18 = 19 psi188 psi Live load plus impactDead load (slab) (Distribution Factor)

M = 12 w L 18 D.F. = (S +2)/32= 12 (62.5) (7.75)2/8

= (7.5 + 2)/32= 5630 lb-in.

= 0.297 (see AASHTO^ A

= MIS Section 3.24.3.1)= 5630/18= 313 psi Impact (I) = 30 percent IF = 1.3

f6 = MIS, Continuity Factor (CF) = 0.80= 5630118 (AASHTO Section 3.24.3.1)_ 313 psi M = (DF)(IF)(CF)(wheel load)

Live load (during deck casting) _ (0.297)(1.3)(0.8)(16,000)(12)M = 12w L 2/8 = 59,280 lb-in.

= l2(50)(7.75)/8 f, = MIS,= 4505 lb-in. = 59,22801132

f, = M/S, = 449 psi= 4505/18 f= M/S,p= 250 psi = 59,2801543

fb = MIS = 109 psi= 4505/18 f, = M/SG= 250 psi = 59,280/124

Dead load (FWS/overlay) = 478 psiM = 12 x 0.1 (w) (L') z Summation: Governing bottom tension

= 12 x 0.1 (35) (7.5) in panel: 188 313 19 478 == 2363 lb-in. 998 psi.

PCI JOURNAL/March-April 1987 35

Prestress

Estimate the number of strands re-quired:Use % in. diameter stress relievedstrands.P 1 = 0.8x0.70x270x0.85

12.8 kips per strandStress reduction required:Load stresses Allowable stresses

998(-212)= 786 psiStrands will be centered in the depth ofthe panel and will, therefore, only besubject to P/A stresses.Estimate the number of strands forstress:

1"al _ No. of strands x 12,800A 786 psi= 12x3

No. of strands = 2.21 per ft of width, forstress or 2.21 x 4 ft = 8.84 (say, 10strands per panel):Consider ultimate:Required moment:M. - 1.3 [M i1 + 1.67(MLL+r)l

= 1.3 [3378 + 5630 + 2363+ 1.67 (59,280) ]

= 143,480 lb-in.My = A *feud (1 0.6p* f,, ,)

[AASHTO Eq. 9-131f * = .fe( 1 0.5p*fglf,)

[AASHTO Eq. 9-17]P * = A a/(bd)Check A * 10 strands per 4 ft width or10 x 0.08514 0.2125 in. 2 per ft.p* = 0.2125/(12x6.5)

= 0.0027f, = 270 [1 0.5 (0.0027 x 270)/4]

= 245 ksiCheck reduction of f 1 *, due to limited de-velopment length:

(fsu)* t=

mx =a D + Jae

(AASHTO Eq. 9-19) 96 _+2x151

2x0.375 3= 229ksi143,480 lb-in.

Consider maximum and minimum steel:Maximum:P * f; If" < 0.30 (AASHTO Eq. 9-20)0.0027 x 229/4 =- 0.155 < 0.3Minimum:M 1,> 1.2M, (AASHTO Section 9.18.2.1)1.2M rr 1.2 [(f r + fn) S , + M ir ]where f is the prestress minus deadload acting on panel.

1.2Mer = 1.2 [(7.5 ^(&Y + 10x12,8003x48188-313)124+5630+33781

= 147,400 lb-in. < 287,000 lb-in.Calculate prestress losses (see AASHTOSection 9.16.2):f, = SH+ES+CR,+CRSSH = 17,000 150 RHAssume a midwest location in which RH= 70.SH = 17,000-150x70

= 6500 psiES = (Eg/E^i)fjjAssuming 10 percent prestress losses atrelease:

0.7x0.9x270x 10x0.085}gar 48x3

= 1.000 ksi or 1000 psiES 28 x 10'' x 1000

33 x 150 1, * x tifo00= 7330 psi

CRC = 12 fefr 7frds= 0+ 4-19

f, 2

= 11 psiCR, = 12x1000-7x11

= 11,920 psiCR, = 20,000-0.4ES-0.2(SH+CR,)

= 20,000-0.4x7330-0.2 (6500 + 11,920)

= 13,380 psifx = 6500 + 7330 + 11,920 + 13,380

= 39,130 psif*e = 0,7x270-39

= 150 ksi

36

Percentage of prestress losses:39,130 x 100

= 20.7 percent0.7 x 270,000which is about 20 percent losses.Therefore, there is no need to recalcu-late losses.

Pf = (1 - 0.207) x 0.7 x 27() x 0.085= 12.7 kips per strand

12.7x10f^` 3x48

= 0.882 ksi or 882 psi

Check stresses (all in psi):At release

(10 percent losses)Place deck Final

Toad frnf, ftn ft, fri f, FrP,JA 1000 1000 882 882 882 882Mmne , 188 -188 188 -188 188 -188

1188 812Allowable: 2400 2400slab 313 -313 313 -313uu. o^ lrm 250 -250

1633 -131Allowable: 2000 -212

Mf.. -4 -19 18Mme. + f -109 -478 449

1270 -116 467Allowable: 2000 -212 1600

Note: tension in the bottom of the cast-in- p = 0.11 sq in. per ft width (AASHTOplace concrete deck will be only -109 Section 9.23.2)

- 4 = -113 psi which is negligible. Use W5.5 wires at 6 in. spacing equaling

Distribution reinforcement in panel: 0.11 sq in. per @ of welded wire fabric.

SummaryThe resulting configuration and reinforcement of the panel is shown below.

ROUGHENED W5.5 WIRES AT 6C-CSURFACE TRANSVERSE

IQ 2701(SI STRANDS AT MID-DEPTH

PCI JOURNALIMarch-April 1987 37

APPENDIX B - APPLICATIONS

Figs. B1 to B5 show how precast prestressed concrete panels were used in 1982 on theJefferson Barracks Bridge (1-55) over the Mississippi River in East St. Louis. The projectrequired 130,000 sq ft of 3 in. deep panels 4 ft wide with lengths of 8 ft 2 in. to 8 ft 7 in.

Fig. B1. Looking west, the high density expanded polystyrene foam (EPS) on 10 ft deepsteel plate girders can be seen. Removing wood forms, over the water in this situation,would have been difficult.

Fig. B2. The EPS being hot-wire cut to the correct fillet height before it is attached to thetop flange.

38

C- 0 C Z

T, H 3 CD O O C a n C CD CD

11

W CD

Fig. B5. The deck panels and steel shear connectors in place ready for reinforcing steeland deck concrete.

Fig. BC On this eleven span steel plate girder bridge over a railroad in St. ClairCounty, Illinois, the narrow flange did not allow the use of EPS. PVC pipes were cutto fillet height and glued to the flange. 2 x 4 in. and 2 x 6 in. boards were wedged (notnailed) against the side of the flange to hold the grout bed in place after panels wereset. Stripping was simple. Hooks with long handles were used from the ground to pullout the bowed transverse wood wedges.

40

Fig. B7. A three span wide flange steel beam bridge over a stream near Peoria, Illinois.The panels were made rectangular and cut in the field to fit the skew.

Fig. B8. An overall view of the same structure shown in Fig. B7 (above). The panelsare in place ready for steel shear connectors, reinforcing steel and dock concrete.

PCI JOURNAL/March-April 1987 41

Fig. B9. Details ai skewed end of a 33 WF steel beam three span bridge in BureauCounty, Illinois. The 45 degree skewed end section was formed and poured full depth inthe field.

Fig. B10. Placing panels at steel beam splice where fillets are small. Notice that smallbolt head must be on top of flange plates. Common ironworker practice is to put bolt headon underside of top flange.

42

Fig. B11. An 18 span 66 ft wide steel plate girder high level structure at Lemont, Illinoiscrosses a highway, a ship canal and a railroad. This structure required 190,000 sq ft of2 1/2 in. thick x 48 in. wide panels. Because of curve at each end, the panels were bevelledon each side. The small crane set the panels after a large crane unloaded the trucksbelow.

Fig. B12. Placing 2 in. thick panels on a 42 in. precast prestressed concrete I beambridge in central Illinois. The EPS form was cut to the required fillet height. It is generallyadvisable to place grout while placing panels to avoid air pockets.

PCI JOURNALIMarch-April 1987 43

Fig, B13. The panels and the EPS are in place on the structure shown in Fig. B12.

Fig. B14. The workman is placing grout ahead of the panel setting.

44

Fig. B15. Placing panels on a precast prestressed concrete ! beam structure. Note how agroup of panels are unloaded from trucks and stored on the beams before lifting eachone into place.

Fig. B16. 3' in. thick panels on a steel plate girder bridge near New Orleans, Louisiana.These are set on steel angles prefabricated to proper fillet height shown in Fig. B2.

PCI JOURNA1,,March -April 1987 45