THE GREAT ATLANTIC & PACIFIC TEA CO. PROCEEDINGS PAPER

Design of theA & P Food Processing Facility

by N. V. Campomanes*

SYNOPSIS

The selection of a precast, prestressed concrete structure for the 35-acrefood processing center for the Great Atlantic & Pacific Tea Company wasmade after extensive research studies of several structural systems. Thesesystems were evaluated on the basis of economy, suitability for the processesinvolved, permanency, and low maintenance costs.

The standard roof module adopted was 30 feet by 50 feet with a pre-tensioned 7 foot 6 inch wide roof double tee section spanning 50 feet, andrectangular post-tensioned beams spanning 30 feet with partial continuityover the columns. Floor double tees and sandwich wall panels were alsoof the same cross section as the typical roof double tee unit. Cast-in-placecolumns fixed at the base and pinned on the top were proportioned on thebasis of ultimate strength design.

Flexural tests made at the site on a typical double tee floor unit 25 feetlong, having a three-inch topping, and one typical double tee roof unit 50feet long, exhibited performance characteristics well above the design re-quirements.

INTRODUCTIONThe Rust Engineering Company

of Pittsburgh, Pennsylvania is cur-rently constructing a Food Process-ing and Packaging Plant at Horse-heads, New York for The GreatAtlantic & Pacific Tea Company.This is the largest prestressed con-crete structure in the world. Thebuilding complex covers an area ofapproximately 35 acres under oneroof and consists of one-story andtwo-story structures (with hangingmezzanine floors) housing the food

The Rust Engineering CompanyPittsburgh, Pennsylvania

processing, packaging, and ware-house areas. Fig. 1 shows a bird's-eye view of the plant.

The decision to use prestressedconcrete as the main constructionmaterial was made after extensiveresearch studies of several structuralsystems had been evaluated. Theevaluation was based on:

1. Economy2. Suitability for the processes in-

volved3. Permanency4. Low maintenance cost5. Fire-resistance

The systems studied were of three

June 1965 19

Fig. 1—Artist's Rendering of A&P Plant

general types: structural steel, cast-in-place concrete, and precast con-crete. A total of ten structural roofsystems were investigated and com-pared in the form of a basic module25 ft. by 40 ft. or a multiple of same.

No system was eliminated fromstudy because it was new; indeed,some of the systems were fairly un-common. But on a project of thissize and cost, it was felt that nosystem should be proposed whichhad not been proven by actual con-struction in this country of sufficientextent to insure freedom from anymajor hidden fault. All of the sys-tems studied passed this require-ment.

The evaluation for suitability orservice was based on such factors as

1. Freedom from cracks andcrevices (insect and vermincontrol)

2. Freedom from niches andledges (cleanliness)

3. Ease of painting

4. Ease of washing and cleaning5. Durability (resistance to cor-

rosion, abrasion, impact, etc.)6. Resistance to damage from

foundation settlement7. Rigidity8. Suitability for support of ran-

dom suspended loads9. Noise reduction

10. Depth required11. Compatibility (how well suit-

ed to installation of piping,wiring, lighting, etc.)

12. Appearance13. Alterability14. Fire-resistance15. Economic life (duration of ex-

pected service without majorrepairs)

16. Insulation value

In order to rate the different sys-tems, a composite numerical ratingor "Suitability Index" was devisedwhich could be taken as a measureof the system's overall ability tomeet all the requirements listed.

20 PCI Journal

Suitability indices were arrived atby assigning a numerical weight, or"Evaluation Factor" of from oneto five, in order of increasing im-portance, to each requirement listed.The Evaluation Factor was multi-plied by a numerical equivalent ofthe system's rating on each require-ment based on zero for "poor", onepoint for "fair", two points for"good", and three points for "excel-lent". The Suitability Index for agiven structural system is then thesum of the products obtained fromthese multiplications.

When listed in the order of theirrelative suitability, in our study thevarious systems lined up as follows:

Suitability Index1. Precast prestressed double tee 1132. Cast-in-place waffle slab 1023. Cast-in-place beam & slab 1004. Precast hollow slab 975. Steel longspan deck & box girder 956. Precast prestressed

cored slab & gypsum 817. Precast prestressed single

tees & steel deck 758. Precast channel slabs and T-cols. 549. Steel deck & continuous beams 47

10. Steel joists & trusses 37

Had the most economical systemturned out to be the most suitable,there would have been no problemin making a selection. Since thiswas not so, it became necessary atthat point to make an evaluationbased upon analysis, experience andjudgment.

Suitability is not so easily eval-uated economically, but it is evidentfrom an examination of the factorsupon which it is based that a systemwhich is low in suitability will bemore costly to maintain, requiremore repairs, and make more dif-ficult the maintenance of the sani-tary standards which A & P requiresin the food processing areas. It was

judged that the better suitability ofprestressed double tees for use inthe food processing areas would,over the life of the buildings, morethan return to A & P its greaterfirst cost.

Therefore, prestressed double teeswere recommended and subsequent-ly approved for the structural roofsystem.

A further investigation of theeconomic effect of module dimen-sional changes was made for theprestressed concrete construction.Both dimensions of the bay werevaried, but as can be seen on Figure2, area seems to be the governingfactor, at least within the length-to-width ratios studied. The curveshows the U-shape which is typicalfor this type of study, with the mosteconomic bay area being in thevicinity of 1500 sq. ft. Also, widercolumn spacings are usually moredesirable from an operational stand-point and equipment arrangement.

Thus, a 30 ft. by 50 ft., rather thana 25 ft. by 40 ft. building modulewas adopted.

A similar investigation was madefor the "Wall Treatments". Sevenwall systems were studied and listedin the order of their relative suit-ability, the various systems lining upas follows:

Suitability Index1. Precast insulated concrete 932. Precast cored slab panels 923. Precast concrete 854. Concrete block & glazed tile 715. Insulated steel panels 596. Concrete block & brick

58

7. Concrete block

54

Since suitability is considered tobe of primary importance in the se-lection of treatments for the foodprocessing areas, precast insulatedconcrete wall panels were recom-mended.

June 1965 21

1.45

1.40

v 1.35

1.25

1.20C apO0 n

PANEL AREA - SQ. FT.

SYSTEM NO. 7

PRESTRESSED DOUBLE TEES

AND

PRESTRESSED GIRDER

Fig. 2—Panel Area vs. Relative Cost Curve

Since precast concrete double teeshad been recommended for the roofsystem, the choice of the same ma-terial for the walls assured that theroof and wall were functional equi-valents with consistent economiclife.

Refer to Fig. 3 for typical roofframing using precast prestressedconcrete double tees and Fig. 4 fortypical sandwich wall panel usingprecast prestressed insulated con-crete double tees.

SUB-SURFACE CONDITIONS

Geologically, the sub-soil at theplant site is chiefly water-laid mate-rial from glacial outwash or deltaformations. Such material showssigns of stratification. Most of the

overburden is quite gravelly but thebody of the soil is chiefly sand andsilt in which gravel and rock frag-ments are embedded.

The development of the sitecalled for a plan of cutting and fill-ing which utilized to some extentthe available site material for fill.Placement of a well-controlled fillhad improved the existing conditionand had added another four feetor more of material which was uni-formly compacted to a higher degreeof density than the original soil.

With respect to support for in-dividual column footings for theone-story structure, footing settle-ments of about one-half inch or lesscould be reasonably expected. How-ever, for the two-story structure,greater footing settlements may be

22 PCI Journal

expected to the extent that differen-tial settlement might cause distressof the superstructure. Bearing thisin mind, the final design of the su-perstructure had to take this possi-bility of differential settlement intoconsideration.

Analysis of soil bearing capacityand settlement of structural founda-tions for the main building indicatedthat spread foundations designedfor an equal contact pressure ofthree tons per sq. ft. would providefor maximum economy in construc-tion cost.

DESIGN ASPECTS

Having adopted a standard roofmodule of 30 ft. by 50 ft., a roofdouble tee 7'-6" wide by 50 ft. anda rectangular girder 18 inches wideby 30 ft. were selected. Because ofthe large magnitude of the project,

the most economical section was thefirst objective of design. Repetitionand uniformity of units were ofprime importance, so the typicalroof double-tee unit, typical floordouble-tee unit, and the wall panelunit have the same cross-section(See Fig. 5). Roebling's 7-wire stress-relieved 270 K select strand wasused for the prestressing tendon.

Bearing in mind that ledges andniches had to be avoided, the pre-stressed girder was designed to al-low the double-tee unit to sit ontop and a composite pour to be cast-in-place to cover up all the openingsand ledges. This composite concretealso served to carry the additionalbending moment induced by the su-perimposed dead load and live load.Although these were originally de-signed as pretensioned beams usingthe same tendons as those used in

Fig. 3—Typical Roof Framing

June 1965 23

Fig. 4—Typical Precast C

the double-tee units, DickersonStructural Concrete Corporation, theprestressed concrete contractor,elected to use equivalent post-ten-sioned beams to suit their precastingschedule. Special Stressteel bars ofType 160 K were used as the pre-stressing tendons. After the post-ten-sioning operation, grout was injectedinto the flexible tubing. The roofgirder was designed for partial con-tinuity over interior columns. Thiscontinuity was achieved by usingtwo No. 10 mild steel reinforcingbars near the top of the compositepour.

The sandwich wall panel consists

24

)ncrete Sandwich Wall Panel

of a standard prestressed double-teeunit with 2-inch styrofoam insula-tion and 2-inch unprestressed con-crete inside facing. To assure acrack-free concrete surface, the twosurfaces were isolated as much aspossible by using expansion jointmaterial at the contact points. Toprevent separation of the two faces,1/4" round smooth dowels were usedwith soft rubber sleeves enclosingthe dowels at the contact points.The rubber sleeves would allow un-restrained relative movement of thetwo faces due to temperature differ-ential between the inside and out-

PCI Journal

TYPICAL ROOF DCU15LE TEE

V-10/2 -9 ^> -^evrws

N O Z 119 5000 Pal cONC,I2 2701 15TRA.NOS3 . `+ 1'

N A.110-SPAN ENO SPAM ;r I3 _

TYPICAL PLOO OUI L.E TEE

IJC. TOP0 PSI CONC.

7 sJ- i^o cox co- 70WWF

-c' I MI(7 -SPAN END SPAN S^

TYPICAL NICH WALL PANEL

-10^ _9 9x^-^WWF

4"G WWF y .t2- /t "2'O STYRAFOAM

12 10 SMOOTH rxwELSINSIDE aj jV WALL.

_SOFT Rue b&RU.StVES 1-0 CEWTER-b

Fig. 5—Typical Double-Tee Sectionsside faces, subjected, a more realistic design

In the design of the columns, pre- of the columns was made based oncast and cast-in-place columns were the ultimate strength concept. Con-investigated and the latter type was siderable savings on concrete cross-selected. The possibility of differen- section, reinforcing bars and form-tial settlement and the necessary re- work were realized by proportioningsistance to horizontal forces induced the columns on this basis instead ofeither by erection forces or wind the working stress concept. Highforces, dictated the design of the strength steel of 60,000 psi yieldcolumns fixed at the base and pinned point was used to further cut theat the top. Knowing the actual loads number of bars used in the columns.to which the superstructure will be _ Concrete design strength was 4,000

June 1965 25

psi in 28 days.

JOINTS AND CONNECTIONS

To provide an effective, uniform,and positive bearing of the pre-stressed girders on the columns,neoprene bearing pads were used.At the expansion joints, a combina-tion of neoprene and teflon bearingpads were used. This consisted oftwo layers of 1/4" neoprene, 100 per-cent bonded to 1/16" Teflon, with theTeflon sides in contact. This combi-nation of neoprene and teflon ismore effective in assuring free-slid-ing action than the laminated formof neoprene bearing pads.

One of the owner's main require-ments was to provide a uniform gridsystem for present and future hang-ing loads. This was achieved by pro-viding a %" hole built-in near thebottom of the stems of the doubletee, spaced 5 ft. on centers, whichprovided 3'-9" spacing in one direc-tion and 5 ft. spacing in the other.To cover the hole when not in use,and to prevent infiltration of roaches,vermin and dirt, a removable plasticplug or cap was inserted at eachside of the stem. Refer to Fig. 6 forprovisions for hanging loads.

The wide spacing of the stems ofthe double-tee units provided neces-sary roof openings for air ducts. Insome special areas where openingshad to be larger than could beflange-cut between stems, single teeswere designed to fit these specialconditions. In situations which couldnot be resolved by using prestressedsingle tees, or double tees, a combi-nation of cast-in-place concrete andprecast concrete was used.

TESTING PROGRAM

Testing Criteria

In order to assure the quality andstructural integrity of the prestressed

26

units, a testing program was re-quired before mass production ofthe units began.

The criteria for acceptance ofthese units was based on the fol-lowing provisions:

50 Ft. Roof Double-Tee

1. No cracking of the concrete atthe design load.

2. No failure of the unit at themaximum specified superim-posed test load equivalent to2.0 times the service live loador 50 p.s.f. The test load to beapplied without shock to thestructure and in a manner toavoid arching of the loadingmaterials.

3. At least 90% recovery of themaximum deflection within 24hours after removal of the testload.

25 Ft. Floor Double Teewith 3 in. Topping

1. No cracking of the concrete atthe design load.

2. No failure of the unit at themaximum specified superim-posed test load equivalent to1.7 times the service live loador 510 p.s.f. The test load tobe applied without shock to thestructure and in a manner toavoid arching of the loadingmaterials.

3. At least 75% recovery of themaximum deflection within 24hours after removal of the testload.

Ultimate Strength Behavior

An extension of the test programwas to load the 50 ft. roof doubletee and the 25 ft. floor double teeto destruction in order to determineits overload capacity and ultimatestrength behavior.

PCI Journal

51WCLE GONCENTfZA7El7 LOA( ON ONE STEM ="ibO* AT ANY POINTOJ 2-STEM%-IZ, O'^EQUALLY0IS'TQIP-vU`wEr TO P^OT.4 STEM .

DP 2-STEM CON►JECTIOI'ISTEM

o

o:. P2ESTRE3SIh1C^ STitAfJf'SPLASTtG cs.P

-- STEMW Q vC A ' V .

3'-9

FUTU E CON N Er,710 Kl

STEM

a Pee-emeeSSIIJ4 TI2AI4o516 TN2CUGH FbOL.TI N ''^, cmt LL OLE ° ^o PENT Ff: K 3 WI fJE

+ t ; _. 1-L 3-5 4

STEM

PE-4T CON JECTON.J

Fig. 6—Provisions for Hanging Loads

1. The failure load shall not occurat less than two times the sumof design dead and live load,nor less than three times thedesign live load alone. If nofailure fracture occurs, the loadcausing a deflection of 1ifr0 of thespan is to be considered thefailure load. (Minimum Stand-ard Requirements for PrecastFloor and Roof Units, ACI711-58)

Test ResultsThe results of the load tests met

all of the above requirements.The roof double tee failed at more

than 158% of its design ultimatebending moment capacity or 3.3times the design live load. Actualfailure did not occur as the middleof the unit deflected 25 in. and.touched the ground.

The floor double tee failed atmore than 185% of its design ulti-

June 1965 27

LOADINCg SEQUENCE

2 1 3 I 2

3 .6 G SPAGe5 @ 7-'0 = 42-0 3-ro

49'- o

TYPICAL ROOF OOUf5LE TEE

5I ZE OF Il4 UT 1'S4x 15 x5-O, wT, tMC31oT 2&5O'

2'-4 4'-8__ = LOI►DI44y SGcQuE►,iGE

4 N■4

® ^ N=4

® Y/V/V/Vi- 2O N■10

N■8

ek'-io -4 ________ 5-io

24=o

TYPICAL. FLOOR DOULE TEE

Fig. 7—Test Loading Procedure

mate bending moment capacity or3.4 times the design live load. Thefailure was induced by the ruptureof the prestressing tendons at mid-span followed by crushing of theconcrete.

Fig. 7 shows the test loading pro-cedure or loading sequence.

Fig. 8 shows the moment vs. de-

flection curve for the typical 50 ft.roof double tee.

Fig. 9 shows the moment vs. de-flection curve for the typical 25 ft.floor double tee.

Fig. 10 shows test load on floordouble tee before failure.

Fig. 11 shows test load on floordouble tee at failure.

28 PCI Journal

250

O0-

2

CALL. M „LT 228.5 K

_

SERIES I -TEST NO.50 ROOF DOUBLE TEE

C LC. M= I24' ^— - a. -v o

DESIGN M N=Y =9l I __

y45PAN/ `` O

M10-SPN / /

// © 24-HR. CREEP

® / ® 24-HR. REBOUND

0.9 1.0 1.5 2.0 2.5 3.0DEFLECTION N IWCHES

Fig. 8—Moment vs. Deflection Curve for 50 Ft. Roof Tee

SERIES I-TEST NO.225 FLOOR. DOUBLE TEE

CLcWITH 3° CONC. TOP

yq SPAN Z {- n^_ O /_^ t.MCRK ` QI' O/O

-- Ao/ESIGN M— -163? / n,'/// /u

ON MID-SPAN / / © 24-HR CREEP

70.5 1.0 1.5 20

g` DEFLECTION 11.1 IKCHES

Fig. 9—Moment vs. Deflection Curve for 25 Ft. Floor Tee

LL2rW'02aWJa

I50

June 1965 29

Fig. 10—Test Load on Floor Tee Before Failure

Fig. 11—Detail of Floor Tee at Failure

CONCLUSIONSThe high suitability for food proc-

essing; the relatively moderate cost;the durability and fire-resistance; thelow maintenance cost; and the ex-cellent load performance character-

istics exhibited in the full-scale loadtests have shown that the choice ofprecast prestressed concrete for TheGreat Atlantic & Pacific Tea Com-pany's food processing and packag-ing plant was a wise one.

Presented at the Tenth Annual Convention of the Pre-stressed Concrete Institute, Washington, D.C., September 1964.

30 PCI Journal