SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

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SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I-REVIEW AND PERFORMANCE OF SPLICES Robert N. Bruce, Jr., PhD Professor of Civil Engineering Tulane University New Orleans, Louisiana David C. Hebert Research Assistant Civil Engineering Department Tulane University New Orleans, Louisiana Effective splicing of prestressed concrete piles can reduce or eliminate many problems associated with the installation of long piles. Proper splicing methods eliminate the need to predict precise pile lengths, and allow extensions of piles when necessary. This report presents the results of an investigation into existing methods presently used in the splicing of prestressed concrete piles. The first part of this report constitutes a review and evaluation on splicing methods developed and used in several areas of the world. The second part of the report, to be published in the next issue of the PCI JOURNAL, describes actual tests and analyses of one of the splices described in this article. 70

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SPLICING OF PRECASTPRESTRESSED CONCRETEPILES: PART I-REVIEWAND PERFORMANCEOF SPLICES

Robert N. Bruce, Jr., PhDProfessor of Civil EngineeringTulane UniversityNew Orleans, Louisiana

David C. HebertResearch AssistantCivil Engineering DepartmentTulane UniversityNew Orleans, Louisiana

Effective splicing of prestressed concrete piles canreduce or eliminate many problems associated withthe installation of long piles.Proper splicing methods eliminate the need topredict precise pile lengths, and allow extensionsof piles when necessary. This report presents theresults of an investigation into existing methodspresently used in the splicing of prestressed concretepiles.The first part of this report constitutes a reviewand evaluation on splicing methods developedand used in several areas of the world.The second part of the report, to be published inthe next issue of the PCI JOURNAL, describesactual tests and analyses of one of the splicesdescribed in this article.

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Robert N. Bruce, Jr. David C. Hebert

BACKGROUND

Effective pile splicing can reduce oreliminate many problems associatedwith the installation of precast pre-stressed concrete piles. Among theseproblems are the:'

1. Need to forecast pile lengths ac-curately, eliminating waste

2. Extension of piles cast short of thelength found to be necessary from fieldresults

3. Cost and difficulty of handlingand transporting long piles

4. Tremendous weight of long piles,and

5. Increased cracking incurred withexcessive handling of long piles.

Proper splicing of prestressed pilingeliminates the need to predict the pre-cise pile lengths and allows extensionsof piles when necessary. Splicing en-ables the use of shorter pile sections;thereby reducing the weight and lengthof pile that is handled and reducing thedanger of cracking due to excessivehandling.

This report represents the results ofan investigation into the present meth-ods of splicing prestressed concrete pil-ing, and the results of actual tests ofcertain splices. Each splice included inthe investigation was studied to deter-mine the performance of the splicedsection compared to the unspliced con-tinuous pile.

The overall effectiveness of a givensplice is dependent upon several fac-tors. Those factors used in evaluatingthe splices examined in this investiga-tion were as follows: size range, fieldtime for splicing, approximate cost ofsplice, availability, construction usage,structural integrity, and structural per-formance.

The data used in the evaluation ofthe splices was generated by the auth-ors for the most part. However, someof the data was furnished by the design-ers and fabricators of a given splice.

The investigation was limited tothose splices commonly used and waslimited to splices capable of being driv-en by pile driving equipment.

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ACKNOWLEDGMENTS

The work on the project was conductedby the Department of Civil Engineeringof Tulane University for the Louisiana De-partment of Highways and in cooperationwith the Federal Highway Administration.

On the part of the Louisiana Departmentof Highways, the work was done under theadministrative direction of James W. Lyon,Jr., research and development engineer;Hollis B. Rushing, assistant research anddevelopment engineer; and Joseph E. Ross,concrete research engineer. In addition,Sidney L. Poleynard, assistant director;David S. Huval, bridge design engineer;James C. Porter, head bridge designer; andLouis A. Garrido, assistant bridge designengineer, all contributed greatly to the in-vestigation.

On the part of the Federal Highway Ad-ministration, the work was supervised byMitchell D. Smith, division bridge engi-neer; and Michael A. Cook, assistant di-vision planning and research engineer.

The investigation was directed by Dr.Robert N. Bruce, Jr., professor of civil en-gineering, as project investigator.

Appreciation is expressed to Prof. JohnK. Mayer of the Tulane University Depart-ment of Civil Engineering for technicaladvice on numerous occasions.

Gratitude is extended to the PrestressedConcrete Products Company for time andmaterials donated to the project.

Appreciation is expressed to the follow-ing individuals and organizations who havecontributed technical background informa-tion and data to this investigation:Alberdi, T. Jr., Florida Department of

Transportation.Anderson, Arthur R., Concrete Technology

Corporation.Andrews, D. A., The Concrete Society

(England).Banks, Paul I., Hawaiian Dredging Com-

pany.Blessey, Walter E., Tulane University.Brandon, N. R., Concrete Pipe Products

Co. Inc.Broms, Bengt, Swedish Geotechnical Insti-

tute.Brown, Thane E., Swan Wooster Engineer-

ing Inc.

Chargar, William, Chargar Corporation.Corley, W. C., Portland Cement Associa-

tion.Davisson, M. T., University of Illinois.Duclos, Louis, Barnard and Burk, Inc.DeFeu A., Cement and Concrete Associa-

tion.Edwards, Harry, Leap Associates Inc.Elliott, A. L., California Division of High-

ways.Fellenius, Bengt H., Torchinsky & Associ-

ates Ltd.Fuentes, Gabriel Jr., Fuentes Concrete

Piles.Fukushima, Yoshikiyo, Nippon Concrete

Industries Co. Ltd.Fuller, F. M., Raymond International, Inc.Gerwick, Ben C. Jr., Consulting Engineer.Goldberg, Donald, Goodkind & O'Dea,

Inc.Guild, C. L., American Equipment Fabri-

cating Co.Hanson, Walter E., Walter E. Hanson

Company.Hedman, S., Akermans Verkstad AB.Henneberger, Wayne, Texas Highway De-

partment.Hirsch, T. L., Texas A & M University.Hunt, Hal W., Associated Pile & Fitting

Corporation.Jenny, Daniel P., Prestressed Concrete In-

stitute.Kennedy, Robert H., Castcon, Inc.Kokubu, Masatane, University of Tokyo.Leonhardt, Fritz, Consulting Engineer.Lin, T. Y., University of California.Lyon, Ethyl V., Portland Cement Associa-

tion.Makita, Hiroomi, Tokyu Concrete Industry

Co., Ltd.Manson, John F., Dravo Corporation.Marier, Gaston, Consulting Engineer.Moretto, 0., Bolognesi-Moretto Engineers.Moses, Warren, Bayshore Concrete Prod-

ucts Corporation.Mouton, William J. Jr., Consulting Engi-

neer.McCalla, W. T., Hamilton Form Company,

Inc.Nordahl, Arne, Swedish Institute for Ma-

terials Testing.O'Donnell, Keith 0., Department of the

Army.Papayoti, G., Raymond International, Inc.Raamot, Tonis, Raamot Associates.

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Severinsson, S., AB Scanpile.Sheppard, David A., Blakeslee Prestressed

Concrete.Shideler, J. J., Portland Cement Associa-

tion.Siess, C. P., University of Illinois.Sjostrom, Orjan, Stabilator AB.Stone, John, Belden Concrete Products

Corporation.Talbot, W. J. Jr., Santa Fe-Pomeroy, Inc.Thorburn, J. Q., Logistics Limited.Trueblood, C. B., Armco Steel Corporation.

Thanks are expressed to John Dane III,Gerald W. Hanafy, Charles H. McGee,Robert J. Motchkavitz, and Daniel B. Nash,students in the Tulane University Depart-ment of Civil Engineering. The manuscriptwas prepared by Mrs. Donna Pickens.

PILE SPLICESPRESENTLY IN USE

Introductory RemarksTwenty pile splices are discussed in

this section. Though each splice hasunique and distinct characteristics, thesplices investigated could be catego-rized generally as follows:

1. Welded Splices2. Bolted Splices3. Mechanical Locking Splices4. Connector Ring Splices5. Wedge Splices6. Sleeve Splices7. Dowel Splices8, Post-Tensioned SplicesThose specific splices that form the

basis of this investigation included:1. Marier Splice (Canada)2. Herkules Splice (Sweden)3. ABB Splice (Sweden)4. NCS Splice (Japan)5. Tokyu Splice (Japan)6. Raymond Cylinder Splice (USA)7. Bolognesi-Moretto Splice (Ar-

gentina)8. Japanese Bolted Splice (Japan)9. Brunspile Connector Ring (USA)

10. Anderson Splice (USA)11. Fuentes Splice (Puerto Rico)12. Hamilton Splice (USA)

13. Dowel Splice (USA)14. Macalloy Splice (Great Britain)15. Mouton Splice (USA)16. Raymond Wedge Splice (USA)17. Pile Coupler Splice (USA)18. Nilsson Splice (Sweden)19. Wennstrom Splice (Sweden)20. Pogonowski Splice (USA)

Description of Individual SplicesThe purpose of this section is to pro-

vide specific information concerningeach individual splice. This informationincludes the origin, fabrication, con-struction, and use of the splice. Eachof the above splices was analyzed andevaluated and compared in terms ofseveral parameters. Basic considerationsincluded size range, field time for splic-ing, approximate cost, availability, andconstruction usage.

The evaluation based on performancedata included driving performance;compression, tension, and flexural re-sistance; fatigue; and corrosion resis-tance. The evaluation was based on ac-tual experimental data obtained fromtests on specific splices. Where no testdata was available (as was the case witha few splices), theoretical analyses weremade.

The tests included driving tests un-der variable conditions, extractions ofpiles, and flexural and shear testing ofthe full-sized extracted piles. Drawingsof each splice are provided to show thebasic concept of the splice, but are notintended to describe particular engi-neering details.

The data used to establish the evalu-ation of individual splices was fur-nished, for a considerable part, by fab-ricators, designers, and proponents of agiven splice. Most of the splices wereproprietary, having one or more pat-ents, United States or otherwise. Thedata furnished was generally favorable.

Data reflecting unsatisfactory per-formance was difficult to obtain. A sta-tus report of the investigation was pre-

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sented to the 1973 Regional Meetingsof the Committee on Bridges and Struc-tures of the American Association ofState Highway Officials, in an attemptto uncover any problem areas with giv-en splices, or with splices in general.Although some general comments weremade by the bridge engineers present,no specific unsatisfactory performancewas reported.

PILE SPLICESINVESTIGATED

Marier SpliceThe Marier splice is a mechanical

splice and is shown in Fig. 1. Smallflexible pins are inserted circumferen-tially into the splice, locking the sec-tions together. Small tolerances must bemet in the fabrication of this splice asexact fits of the locking pins are neces-sary for good performance of the splice.

The Marier splice requires anticipa-tion in the preparation of the pile sec-tions. Male and female steel caps arecast into the ends of the piles. Holes inthe caps allow prestressing strands topretension the piles. The prestressingstrands are not mechanically connectedto the pile caps. The cap is secured tothe piling by use of dowel bars. Thenumber and length of dowels requiredto anchor the cap to the pile is depen-dent on the size of the pile and thestructural capacity of the pile section.The steel caps are circular in shape;the piles need not be circular. TheMarier splice has been successfully usedwith octagonal piles.

The female section is driven in thefield with the use of a driving shoe. Theshoe fits in the female end and is lockedto the bottom section with a lockingpin. When driving is completed, thedriving shoe is removed by pulling thelocking pin from the bottom splice cap.The top section is then set into position.Four flexible locking pins are driven cir-

cumferentially into the splice to com-plete it. The male cap is a tighter fitthan the driving shoe because the pinsare not to be withdrawn.

The splice was patented in 1969 byGaston Marier of Princeville, Quebec.2The time required to complete thesplice is minimal. Reports indicate thatthe Marier splice has been successfullyused in Canada.

Herkules SpliceThe Herkules splice is a mechanical

splice and is shown in Fig. 2. The spliceis available for hexagonal, round, orsquare sectional shapes. It is presentlyused for reinforced concrete piling, butcan be adapted for prestressed concretepiling as well. The manufacturers de-sign the spliced Herkules pile to devel-op the same flexural capacity as that ofthe unspliced pile, and report that jointstrength in compression and tension isdesigned to withstand all conditions ofhard or soft driving.

The Herkules splice requires priorpreparation of the concrete piling. Steelmale and female caps are cast into theends of the piles. The female cap isdriven down with the bottom pile sec-tion. A special driving shoe is requiredto prevent damage to the female cap.The top pile section, with the male endattached to it, is then stabbed into thefemale cap.

As shown in Fig. 2, the male cap hasa steel pin which protrudes at the tip.This pin acts as a stabbing guide andaids in the alignment of the male andfemale caps during splicing operations.The top section is rotated, locking thepiles together mechanically. Two lock-ing pins are inserted into the splice,maintaining the locked position. Thefield time required to complete thesplice is minimal and the proceduresimple.

The Herkules splice is manufacturedby A. B. Scanpile, Gothenberg, Sweden.The splice is patented and may be usedapart from the Herkules pile. A. B.

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Scanpile reports 30 million ft of Her-kules piles have been used with theHerkules splice over the past 10 years .3

ABB SpliceThe ABB splice, shown in Fig. 3, is a

mechanical splice. It is used primarilyfor square piling but may also be usedwith round, hexagonal, octagonal, orhollow cross sections. The ABB spliceis used on conventionally reinforced pil-ing, but it can be adapted to prestressedconcrete piles.

The upper and lower pile sections areidentical. The splice consists of lock-blocks welded to the reinforcing rodsand cast with the piles. Reports indicatethat the reinforcing rods are not weak-ened by the weld, and the joint is atleast as strong as the reinforcement.The block is coated with a corrosiveprotective material to insure long life ofthe pile.

A special driving shoe is required toprotect the protruding joint block dur-ing driving. The top section is alignedproperly and lowered into the bottompile section. The splice is completed bydriving special locking pins into thejoint blocks, which remain in place.When in position, the locking pins ex-ert stresses in the joint blocks whichdraw together the ends of the pile sec-tions. The face of the splice is pre-stressed to some extent. The time re-quired to complete the splice is mini-mal, and the procedure is simple.

The ABB splice is manufactured andpatented by the Stabilator firm of Swe-den.4 According to reports, the ABBand Herkules splices cover the need ofpile joints on the Scandinavian andWestern European markets. Stabilatorreports the strength and rigidity of theirjoint is equal to that of a continuouspile.

NCS SpliceThe Nippon Concrete Systems (NCS)

splice is a welded splice shown in Fig.

4. The splice is manufactured in con-junction with the NCS prestressed con-crete piles. These piles are prestressedby the pretensioning method. The pre-stressing strands are tensioned; then thepiles are centrifugally spun.

The NCS splice consists of two steelcaps cast into the ends of the sectionsto be spliced. The caps are connectedto the pile tips in two ways. First, thecaps have dowel bars attached to an-chor the cap to the pile. The numberand length of the dowels is a functionof the pile dimension and strength. Sec-ondly, the prestressing strands are me-chanically fastened to the steel cap byuse of a buttonhead. The buttonheadcan be seen in Fig. 4 at the tip of thepile section. This procedure is uniquein that the full prestress of the pile iscarried into the end of the pile section.

The bottom section is driven down,and the top section is properly alignedon it. The sections are then welded to-gether with a groove weld. NipponConcrete Systems has developed threemethods of welding the joint: (1) handoperated, (2) semi-automatic, or (3) full-automatic joint welding. Corrosion isaccounted for by increasing the size ofthe groove weld.

The Nippon Concrete Industries re-ports excellent performance of thesplice. 5 The company has constructed aplant in Everett, Washington, for themanufacture of the NCS piles andsplices. Acceptance and usage of theNCS splice is anticipated in the PacificNorthwest.

Tokyu SpliceThe Tokyu splice is a welded splice

used in conjunction with piles pre-stressed with steel bars instead ofstrands. Seventy percent of the bars arelow carbon steel hardened by high fre-quency electricity; the remaining 30percent are high carbon steel bars hard-ened by drawing. This splice is shownin Fig. 5.

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The splice itself consists of male andfemale steel caps cast into the piles. Themale and female caps are fitted throughthe prestressing bars. These bars arethreaded at the ends, enabling bolts tofasten the cap to the end of the pile se-curely. The tightening of the bolts is, ineffect, carrying the prestressing to thetips of the pile, similar to the NCSsplice. The male cap has stabilizingguides to help align the two sectionsduring construction.

The bottom section is driven in thefield with the aid of a special drivingshoe to protect the splice. The top sec-tion is stabbed into the bottom sectionand positioned. Fig. 5 shows how thestabbing guides are helpful during stab-bing and alignment of the sections. Thesplice is completed by butt welding thepieces together.

The Tokyu welded splice is manufac-tured and patented by the Tokyu Con-crete Industry Co., of Tokyo, Japan,and it is used in conjunction with theirprestressed concrete piles. The splicecan be used on various sizes of cylinderpiles. It is reported that the Tokyusplice develops the full bendingstrength of the unspliced section s Testsreported indicate that the temperaturesreached during the welding of thesplice are not detrimental to the con-crete or the prestressing bars.

Raymond Cylinder Pile SpliceThe Raymond cylinder pile splice is

a welded splice, as shown in Fig. 6. Theinability to handle long sections of pre-stressed cylinder piling on land in-duced development of this splice.

The cylinder pile splice consists oftwo steel ring caps which are cast intothe ends of the spun concrete piles. Thesteel caps are connected directly to thepiling by use of dowel bars threadedinto the cap. The cap is designed withopenings to allow the post-tensioning ofthe pile.

The post-tensioning is performed bythe threading of the prestressing

strands through the cast holes in the pil-ing and the steel splice cap. The strandsare stretched and grouted to apply theprestress to the pile. The prestressingcables are not intended to anchor thecap to the pile.

In the field, the bottom section isdriven with the aid of a special drivingshoe. The shoe fits over the splice capand is tack welded to allow driving ofthe bottom section without damage tothe splice. After the bottom section isdriven, the driving shoe is removed andthe two sections are then butt-weldedtogether. If stability problems exist,leads are used to aid the alignment pro-cedures. Tests of the splice indicate to-tal time required to complete the spliceto be 1 1/z hours.

The cast steel driving splice was de-signed by Walter E. Blessey for Ray-mond Concrete Pile Co., with Shell OilCompany as cosponsor. As a result oftests performed at Tulane University,the dowel bars were lengthened from18 to 36 in.

Bolognesi -Moretto SpliceThe Bolognesi-Moretto splice is a

welded splice illustrated in Fig. 7. It ispresently used in the splicing of rein-forced concrete piles and is included inthe investigation because of its adapta-bility to prestressed piles.

The lower pile section is cast with a1 -in, plate anchored to the pile tip bymeans of dowels. Four steel angles arewelded to the plate and extended invarying lengths into the pile. The spliceis unique in that the dowels are anglesrather than bars.

The top pile section is cast in muchthe same manner; however, the baseplate in the top section is somewhatsmaller in size than the bottom plate.This enables the two plates to be weld-ed together by a fillet weld. Fig. 7shows the alignment of the plates andthe fillet weld required to make thesplice.

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The bottom section is driven down toa splicing position. The top section is seton the bottom plate and aligned. Thetwo plates are then welded togetherwith a fillet weld. An epoxy cover pro-tection is spread over the weld andsplice area. This is done to protect thesplice from corrosion. Driving is thenresumed.

Bolognesi-Moretto Consulting Engi-neers of Buenos Aires, Argentina, de-signed and patented the splice. Reportsindicate the the splice can be completedwithin 30 to 40 minutes.8 Drawings il-lustrate the splice used for 15-in. squarereinforced concrete piles. Test data asto the performance of this splice werenot available at the time of this report.

Japanese Bolted SpliceThe Japanese bolted splice is shown

in Fig. 8. It is presently used in thesplicing of reinforced concrete piling.It is included in this study because ofits adaptability to prestressed concretepiling. The principle of the bolted spliceis simple, but the details are relativelyelaborate.

Preparations for the bolted splice in-volve the casting of two steel pieces intothe ends of the piling. Both pieces arefastened to the ten reinforcing bars ofthe piling. The bottom splice piece alsohas ten dowel bars attached whichserve as additional anchorage for thesplice. The upper splice section haseight dowel bars which provide addi-tional anchorage to the pile section.Eight bolts, which are extensions ofthe eight dowel bars, protrude from thesplice section.

The field work involves the driving ofthe bottom pile section in place. Testsperformed on this splice emphasize thecare necessary in choosing a cushionmaterial and in driving the pile sections.The top pile is guided into place overthe lower section. The eight bolts actas stabbing guides during splicing. Theeight bolts are then fastened, locking

the two sections together in preparationfor additional driving. Reports indicatethat the tightening of the bolts pre-stresses the face of the splice to someextent.9

The bolted splice is made in Japanand can be used for various sizes ofpiling. Nippon Concrete Industries, Co.,Ltd., produces the bolted splice in con-junction with its precast reinforced con-crete piles. Consideration should be giv-en to corrosive effects, since the steel inthe splice is exposed.

Brunspile Connector RingThe Brunspile connector ring is a

wedge splice used to join prestressedconcrete piles. 10 Prior preparation ofthe Brunspile consists of casting a roundsteel ferrule at the end of the pile. Smalltolerances must be met in the fabrica-tion of the connector ring. A good fit ofthe ring to the steel ferrules is necessaryfor the proper performance of thesplice.

The Brunspile connector ring acts asa wedging sleeve, as shown in Fig. 9. Inthe field, the bottom pile section is driv-en down, leaving the steel ferrule ex-posed. The wedge connector is thentapped onto the steel ferrule. A 1-in.impact plate is placed between the pilesections within the connector ring. Thetop pile section is guided into the seat-ed connector ring. At this point, drivingis begun. Initial blows of the pile driverwedge the sections together, complet-ing the splice.

The Brunspile connector ring is dis-tributed by the Associated Pile and Fit-ting Corporation and Belden ConcreteProducts Co., Inc. Both the Brunspileand the Brunspile connector ring arecovered by United States patents. Theconnector ring has been used extensive-ly and satisfactorily by Associated Pileand Fitting Corporation with steel pipepiles. Its use has not been as extensivewith prestressed concrete piles. Theconnector ring was not designed as a

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tension splice for prestressed concretepiles.

Anderson SpliceThe Anderson splice is a sleeve splice

developed for prestressed concretepiles. The steel sleeve is made to fittightly around the pile, as shown in Fig.10. Fabrication requires small toleranc-es to assure the tight fit of the sleeve onthe piles. The friction between the pilesand the sleeve is required for properalignment and performance of the pil-ing. It can be fabricated for varioussizes and shapes of piling, with thethickness of the sleeve as a function ofthe diameter of the pile. The pile itselfrequires no special preparation for splic-ing.

The installation of this splice in thefield is simple. First, the steel sleeve isdriven over the head of the bottom pile.A plywood pad, cut to the shape of thepiling, is placed between the bottomand top pile sections. This acts as acushion during driving.

The top pile is driven into the sleevewith a tight fit. If this is not possible,two halves of the sleeve may be weld-ed together over the pile. If the splicemust develop tension, it is reported thatepoxy resin can be injected into thespace between the piles and the splicesleeve. The friction between the pilesand the sleeve is not enough to developsignificant tensile forces.

The Anderson sleeve splice was de-veloped by Dr. A. R. Anderson of Ta-coma, Washington. It has been used bystate agencies and various architectsand engineers in the state of Hawaii.Approximately 120,000 ft of prestressedconcrete piles have been driven on stateand private projects in Hawaii in thelast 5 years with the use of the Ander-son sleeve splice."

Fuentes SpliceThe Fuentes splice is a sleeve splice,

as shown in Fig. 11. It is presently used

to splice 10-in. diameter reinforced con-crete piles. Modifications in the splicecould enable the Fuentes splice to beused on prestressed concrete piles.

The Fuentes sleeve splice does re-quire prior preparation of the concretepiles. A steel band is first welded to thepile reinforcement. The weld is made18-in, from the splice on both the bot-tom and top pile sections. The amountof welding required to connect the bandto the pile reinforcement is dependenton the tensile forces expected in thepile.

The steel band is cast with the pile,exposing its outer surface. A thin steelsleeve is then placed on the bottom sec-tion and welded to the steel band. Thiscompletes the prior preparation neces-sary in the splice.

The bottom pile section is drivenwith a special mandrel. This mandrelprotects the sleeve section that is to re-ceive the male end of the next pile sec-tion. The top pile is inserted into thesleeve, and the sleeve is welded to thetop pile. The only work required in thefield to make the splice is the weldingof the sleeve to the top pile section.Driving is then resumed.

The Fuentes sleeve splice is used inconjunction with the Fuentes ConcretePile. It was developed by Gabriel Fuen-tes, Jr., of Puerto Rico. 12 The pile andsplice are patented in the United Statesand abroad. Shorter pile sections can behandled more easily and do not requirelarge pile driving rigs.

Hamilton Form Company SpliceThe Hamilton Form Company splice,

shown in Fig. 12, is a sleeve splice. Itwas designed specifically for 36-in, out-side diameter cylinder piles with 4-in.thick walls.

Unlike most other splices, no priorpreparation of the piles is necessary.The splice consists of two semi-circularsleeve sections 8 ft in length. Small steelextensions are secured to the sleeves by

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the welding of gusset plates. These ex-tensions are used to receive the boltswhich clamp the semi-circular sectionstogether. This arrangement is shownclearly in Fig. 12.

In the field, the lower pile section isdriven in a normal procedure. The topsection is lowered into position and thenproperly aligned. The sleeve sectionsare positioned around the joint. Boltsare threaded through the holes and aretightened with torque wrenches. Timerequired to complete the splice is onehour to ninety minutes.

The Hamilton Form Company ofFort Worth, Texas, designed the splicefor the piles of the McBride Bridge inBritish Columbia, Canada. The originaldesign called for a 1/4-in, thick sleeve,but this was increased to 3/s in. at therequest of the British Columbia Depart-ment of Highways. The piles were driv-en in —30 F temperatures.

Reports point out the fact that thepile withstood an axial pull of 550 kipsand was tested in flexure until visiblecracking of the pile occurred. 13 A pat-ent was never applied for, so the spliceis public domain.

Cement-Dowel SpliceThe cement-dowel splice is shown in

Fig. 13. A variation of this splice is theepoxy-dowel splice. The concept of thesplice is simple. The choice of materialsused to anchor the dowels to the pilingsis of prime importance. Some materialsare effective in anchoring the dowels,but require an excessive setting time,therein disrupting driving. Other ma-terials set quickly but are ineffective inanchoring the dowels or withstandingdriving forces.

The cement-dowel splice in this in-vestigation was made using Florok Plas-ticized Cement, manufactured by theChargar Corporation of Hamden, Con-necticut.

The bottom section of the splice hasholes which receive the dowels. These

holes may be cast with the pile ordrilled in the field if necessary. The topsection is cast with the dowel bars inthe end of the pile, as shown in the fig-ure. The number and length of dowelbars is dependent on the pile size andstructural capacity.

The bottom section is driven with nospecial consideration. The top section,with the dowels protruding from theend, is guided and set in position overthe bottom section. The dowels act asstabbing guides. Once in position, a thinsheet metal form is placed around thesplice. The cementing material is thenpoured, filling the holes of the bottomsection and the small space between thepiles. The form can be removed after15 minutes and driving resumed.

The splice is not patented. It hasbeen used in New York14 and Florida.15

Macalloy SpliceThe Macalloy splice is a post-ten-

sioned splice,ls applied to prestressedand reinforced concrete piling. Macal-loy prestressing bars are coupled con-tinuously across the joint, fully pre-stressing it.

Preparation is extensive. The lowersection is cast with 1 1/z-in. groutingducts to contain the Macalloy bars andwith holes at the pile ends to receivethe dowels from the top section. Thebars are anchored to the bottom sectionby a sleeve at the ends of the bars, andthey extend out from the top of the pile.The top section is cast with 1%-in.grouting ducts and high-tensile strengthdowels. Macalloy bars are then thread-ed through these ducts. Details of thesplice are shown in Fig. 14.

A special driving helmet is needed toprotect the protruding Macalloy bars inthe bottom section. After driving thebottom section, the top section is posi-tioned over the bottom; and threadedMacalloy bars are then screwed intomechanical couplers. A jointing com-pound is spread over the head of the

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bottom pile and into the holes whichreceive the dowels, taking care to keepthe grouting ducts clear. The top sec-tion is lowered and seated.

The Macalloy bars are stressed withhydraulic jacks, post-tensioning the pil-ing. The bars are wedged and drivingresumed. Top sections of 40 ft and pilesup to 185 ft in length have been suc-cessfully installed with this splice.

The Macalloy splice is patented andis used in Great Britain. 17 The structur-al capacities of the spliced section arevirtually the same as those of an un-spliced section. Tests of the Macalloysplice indicate that this method of splic-ing is practical.

Mouton SpliceThe Mouton splice is a combination

splice. It is illustrated in Fig. 15. It iscompleted by wedging a pin connectorinto connector sleeves which are castinto the ends of the pile sections. Thepin connector is mechanically wedgedinto position when the splice is made.

The connector sleeve is cast into theend of the pile along with a cast ironhead. A %-in, layer of insulation ma-terial surrounds the connector sleeve.This allows the pin to expand andwedge itself into position without crush-ing the concrete surrounding the sleeve.Reports indicate that the fabricationand casting of the connector sleeves iscritical for proper performance of thesplice.

In the field, the bottom section isdriven down and the top section set intoposition over the driven pile. The pinconnector is placed within the connec-tor sleeves of the pile sections. The toppile is then rotated for proper align-ment with the bottom section. As thetop section is lowered onto the lowersection, the wedges in the tips of thepin connector are activated and expandtransversely. The wedging action iscomplete when the sections are touch-ing. The pin connector is now wedged,

and the splice is complete. Field timerequired to complete the splice is mini-mal and the procedure is simple.

The Mouton splice was developed byWilliam J. Mouton, Jr., and patented in1972. 18 It may be employed with vari-ous shapes of piling and is presentlyused in conjunction with the Tri-Pile, atriangular prestressed concrete pilewhich is patented.

Raymond Wedge SpliceThe Raymond wedge splice is a com-

bination sleeve and wedge splice. It isillustrated in Fig. 16. The splice is simi-lar to a "mortise and tenon" splice 19 andis used with prestressed concrete piles.

Preparation of the piles for this spliceis necessary. The end of the bottom pilesection is cast with a pipe sleeve. Thetop section is also cast with a pipesleeve, but this sleeve is constructed dif-ferently. A portion of the sleeve is im-bedded in the tip of the pile, while theend of the sleeve is not filled with con-crete. This sleeve has square holes cutout for the insertion of the steel wedgesduring splicing. Fig. 16 shows the con-struction of the pile tips clearly.

The lower section is driven into po-sition for the splice to be made. Thetop pile section is lifted into position.The pipe sleeve of the top section islowered over the smaller pipe sleeve ofthe bottom section. After proper align-ment, steel wedges are driven throughthe holes of the outer sleeve. This pro-duces a tight fit between the pipesleeves. Once in position, the wedgesare welded in place to prevent move-ment during driving.

This splice was developed and pa-tented by Raymond International, Inc.,which has used the splice with 16%-in.octagonal prestressed piles. 20 Thissplice can be adapted for use with othersizes and shapes of prestressed concretepiles. Prestressed concrete piles 175 ftlong were successfully spliced in Seat-tle, Washington, using this splice.

80

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Pile Coupler SpliceThe Pile Coupler Splice shown in

Fig. 17 was developed and tested in1974, and consists of a steel split ringconnector which is used to join twolengths of prestressed concrete piling.Prior preparation of the Pile CouplerSplice includes the casting and anchor-ing of steel plates into the ends of thesections to be connected. Studs are usedto anchor the splice plates.

The tension band split ring connectorcan be in one piece, or it can be fabri-cated in two pieces. The connectingband is C-shaped and fits into groovesin the steel plates. A good fit of the con-necting band to the steel plates is nec-essary for the proper performance ofthe splice.

In the field, the bottom pile sectionis driven, leaving the steel plate ex-posed. The top pile section is guidedonto the bottom section by a dowel, andthe connecting band is fitted to the bot-tom and top pile sections. The connec-tor band is then closed with a doublebeveled weld.

The Pile Coupler Splice was devel-oped and tested by Marine ConcreteStructures, Inc.; and a United Statespatent has been applied for. Tests indi-cate that the splice, if properly an-chored, is effective in developing thestrength of the prestressed concretepile.

Nilsson SpliceThe Nilsson Splice was developed

and patented by Jan Nilsson and StenNilsson, and is illustrated schematicallyin Fig. 18. It consists of two steel plateswhich are mutually similar and comple-mentary to each other in such a mannerthat each one of the plates can be fittedand engaged to the corresponding plateon the end of the other pile section.Since the two fittings forming the jointare mutually alike, the jointing work issimplified, and economies can be real-

ized in the cost of production of the fit-tings.

The portions of the fitting which ac-complish the interlocking are providedwith undercut edges which engage eachother by means of a sliding ability.

The jointing plates are provided withrecesses which, in interlocked position,are so located that they face each otherfor the purpose of forming a channelinto which a locking bar is placed tolock the two sections together.

The Nilsson Splice is capable of de-veloping the strength of the prestressedconcrete pile, provided that it is prop-erly anchored to the pile section bymeans of the steel sleeve shown in thefigure. The field time required to makethe splice is approximately 20 minutes.

The splice is shown for circular piles,but can be adapted for piles of othercross section configurations.

Wennstrom SpliceThe Wennstrom Splice is a wedge

splice which was invented by Elof Al-got Wennstrom of Orebro, Sweden, andis schematically illustrated in Fig. 19.

Opposing steel plates are anchoredinto the pile section to be spliced. Thesesteel plates are provided with register-ing grooves which extend inwardlyfrom the edges of the steel plate mem-bers and are of dovetailed cross section.The grooves are designed to accomo-date the locking wedges shown, whichare of double dovetail configuration incross section. At their inner ends, thewedges have projections which cooper-ate with curved recesses at the innerends of the grooves. As a result, thewedges when driven into the grooveswill be reliably anchored to the plate-shaped members.

It is reported that the driven wedgesare so anchored that there is no possi-bility of the wedges coming loose andsliding out.

The analysis of this splice indicatesthat it is effective in developing the

PCI Journal/September-October 1974 81

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strength of the prestressed pile, if thesplice plates are properly anchored. Thetime required to make the splice is ap-proximately 20 minutes.

Pogonowski SpliceThe Pogonowski Splice illustrated in

Fig. 20 was invented by No C. Pogo-nowski, Paul D. Carmichael, and Ed-ward E. Bodor. The patent assigns thesplice to Texaco Inc.

This mechanical locking splice wasdesigned to be particularly adapted foruse in offshore or similar applications,where a hostile environment or a se-vere corrosion problem is a pertinentfactor. The pile comprises an elongatedmember formed essentially of a seriesof concrete pile sections.

A metallic cap carried at each pilesection end is adapted to engage and befixed to a corresponding cap on the nextsucceeding pile end thus forming a rig-id connection between the two sections.The metal joint thus formed betweenthe concrete sections is then isolatedfrom its surroundings by means of anenclosing barrier formed on the pile toprotect the joint from corrosion.

The splice is especially applicable toprestressed concrete cylinder piles.

ANALYSIS OFSPLICES

There is a variation of the behaviorof the various splices under field con-ditions. Some may fail directly in thejoint, while in other cases failure resultsfrom bond failure of the dowels anchor-ing the splice to the piles. Lack of abil-ity to anchor and develop the dowelscauses the latter problem. In some in-stances, failure occurs completely out-side of the spliced region. Splice sys-tems that develop strengths greaterthan the piles themselves are usuallycostly.

Each splice in this report was ana-lyzed to determine its structural capac-ity as compared to that of the unsplicedpile. The piles are evaluated as structur-al members, even though the piles arejust one part of a soil-structure interac-tion. Capacities of pile-supported struc-tures are often governed by soil condi-tions, and not by the structural capaci-ties of the piles.

The comparative strengths of thespliced and unspliced sections weremeasured in terms of compression, ten-sion, and flexure. The efficiency of anyparticular splice was computed to bethe strength of the spliced section com-pared to the strength of the unsplicedsection; and is represented as a per-centage. The strength of the splicedsection was considered to be thestrength of the splice in compression,or in tension, or in flexure. The strengthof the unspliced section was consideredto be the strength of the section in com-pression, or in tension; or the strengthat which flexural cracking occurred.Piles are usually designed to preventundesirable cracking. Those splice sys-tems, in which cracking of the fully pre-stressed pile sections occurred beforedistress in the splice, were consideredto be 100 percent effective in develop-ing the cracking load for the splicedpile.

Individual costs of the splices are notdealt with directly in this report, but in-formation supplied by this investigationwill give some indication as to the rela-tive costs involved. Knowledge of thepreparation of piles, the availability ofthe piles, field time required for thesplice, and fabrication of the splice areall beneficial in determining costs. A de-tailed account of the actual costs in-curred in the utilization of each splicewas beyond the scope of this investiga-tion.

(Text continued on p. 93)

82

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SOURCE OF INFORMATION

GASTON MARIERP.O. BOX 549PRINCEVILLEQUEBEC, CANADA

FIG. I MARIER SPLICE

Page 15: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

FIG. 4 NCS SPLICE

IIII

SOURCE OF INFORMATION

NIPPON CONCRETE INDUSTRIES CO., LTD.SUMITOMO SHINBASHI BUILDING8-3 SHINBASHI 1-CHOMEMINATO-KU, TOKYO, JAPAN

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STABILA'IOR ABBOX 46BROMMA 1SWEDEN

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Page 16: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

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SOURCE OF INFORMATION

TOKYO CONCRETE INDUSTRY CO. LTD.TANSIKE - TOKYO BUILDINGNO. 1-1-14, AKASAKA,DIINATO-KU, TOKYO, JAPAN

SOURCE OF INFORMATION

WALTER S. BLESSPYTULA'.NH UNIVERSITYNIil ORLLANSLOUISIANA

C I FIG. S TOKYU SPLICI I FIG. G RAY IONll CYLINDER PILH SPLICE

Page 17: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

000

SOURCE OF INFORMATION

BOLOGNESI-MORETTOLUIS SAENZ PENA 250BUENOS AIRESARGENTINA

SOURCE OF INFORMATION

NIPPON CONCRETE INDUSTRIES CO., LTD.SUMITOMO SHINBASHI BUILDING8-3 SHINBASHI 1-CHOMEMINATO-KU, TOKYO, JAPAN

FIG. 7 BOLOGNESI-MORETTO SPLICE

Page 18: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

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SOURCE OF INFORMATION

BELDEN CONCRETE PRODUCTS, INC.P.O. BOX 607METAIRIELOUISIANA

FIG. 9 BRUNSPILE CONNECTOR RING

Page 19: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

SOURCE OF INFORMATION

HAMILTON FORM COMPANY, INC.P.O. BOX 13466FORT WORTHTEXAS

FIG. 12 HAMILTON FORM COMPANY SPLICE

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Page 20: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

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F PIPE CORPORATION CORPORATION

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THE CONCRETE SOCIETYTERMINAL HOUSEGROSVENOR GARDENSLONDON, ENGLAND

c I FIG. 13 CEMENT-DOWEL SPLICE I PIG. 14 MACALLOY SPLICE

Page 21: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

FIG. 16 RAYMOND WEDGE SPLICE

SOURCE OF INFORMATION

RAYMOND INTERNATIONAL INC.P.O. BOX 22718HOUSTONTEXAS

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II^1 WILLIAM J. MOUTON, JR.,IY ° ` I

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Page 22: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

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MARINE CONCRETE STRUCTURES, INC.P.O. BOX 607METAIRILLOUISIANA

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STEN B. NILSSON1 BRITTSOMMARGATANCUTEBORGSWEDEN

FIG. 18 NILSSON SPLICE

Page 23: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

to

SOURCE OF INFORMATION

BLOT A. WENNSTROMOREBROSWEDEN

FIG. 19 WENNSTROM SPLICE

SOURCE OF INFORMATION

IVO C. POGONOWSKIHOUSTONTEXAS

FIG. 20 POGONOWSKI SPLICE

Page 24: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

SUMMARY OFSPLICES

Table 1 contains information on eachsplice. The sources of the informationare varied. Most of the data was gath-ered from general correspondence withthe manufacturer or designer of thesplice. Data on the strength of thesplices was obtained in three ways:from tests conducted during this inves-tigation; from experience and tests con-ducted by others; and from theoreticaland analytical studies.

Information gathered on the splicesstudied during this investigation was forthe most part favorable. There was lit-tle difficulty in obtaining favorable re-sults. Unfavorable results, however,were not as readily available and weredifficult to obtain.

With reference to those splices listedin Table 1, all are patented with threeexceptions. Those splices not patentedinclude the:

—Anderson Splice—Hamilton Form Splice—Cement Dowel Splice

Prior preparation is required for allsplices with two exceptions. Thosesplices not requiring advance prepara-tion of the pile sections include the An-derson Splice and Hamilton FormSplice. Other data is as tabulated.

It is of importance to note that thestrengths indicated for individual splic-es are dependent on close control andproper procedures in making the splice.Careless workmanship or improper fieldprocedures can result in significant de-viations from the strength levels indi-cated.

CONCLUSIONS ANDRECOMMENDATIONS

Marier SpliceCare and precision in the fabrication

of the male and female caps and thelocking pins are necessary for properperformance of the splice. Any slightvariation in the tolerances may resultin the failure of the splice. The use ofthe splice must be anticipated so thecaps may be cast with the piles.

Herkules SpliceThis has been found to be an effec-

tive method of splicing reinforced con-crete piles. It is felt that only minormodifications would be necessary toadapt the Herkules splice to prestressedconcrete piles. Anticipation of the useof this splice is necessary because themale and female caps cannot be in-stalled in the field.

ABB SpliceThe ABB splice can be used with

various shapes of piles. It can be adapt-ed to prestressed concrete piles. Thesteel caps cast in the ends of the pilesections are symmetrical, thus eliminat-ing any confusion in identifying the sec-tions. Extensive use of the splice inWestern Europe is an indication of thiseffective splicing technique.

NCS SpliceAnalysis and extensive tests of this

splice point out the excellent perfor-mance of the splice. The buttonheadprocess is important in carrying the fullprestress into the splice region. Theconstruction of a plant in Everett,Washington, should make the NCS pileand splice a competitive one in the Pa-cific Northwest. Modern welding tech-niques reduce the time normally re-quired by hand welding.

PCI Journal/September-October 1974 93

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TABLE 1. SUMMARY OF SPLICES

Name of Splice Type OriginApproximateSize Range,

ApproximateField Time,

Strength

Percent Percent Percentin. (cm) min. Compressive Tensile Flexural

Cracking

Marier Mechanical Canada 10-13 (25-33) 30 100* 100* 100*

Herkules Mechanical Sweden 10-20 (25-51) 20 100** 100*00* 100**

ABB Mechanical Sweden 10-12 (25-30) 20 100** 100** 100**

NCS Welded Japan 12-47 (30-119) 60 100** 100** 100**

Tokyu Welded Japan 12-47 (30-119) 60 100** 100** 100**

Raymond Cylinder Welded USA 36-54 (91-137) 90 100** 100** 100**

Bolognesi-Moretto Welded Argentina Varied 60 100* 55* 100*

Japanese Bolted Bolted Japan Varied 30 100** 90** 90**

Brunsplice Connector ring USA 12-14 (30-36) 20 100** 20* 50*

Anderson Sleeve USA Varied 20 100* 0* 100*

Fuentes Welded sleeve Puerto Rico 10-12 (25-30) 30 100** 100* 100*

Hamilton Form Sleeve USA Varied 90 100* 75** 100**

Cement Dowel Dowel USA Varied 45 100** 40** 65**

Macalloy Post-tensioned England Varied 120 100* 100* 100*

Mouton Combination USA 10-14 (25-36) 20 100* 40* 100*

Raymond Wedge Welded wedge USA Varied 40 100* 100* 100*

Thorburn — Scotland No information available on this splice

Pile Coupler Connector ring USA 12-54 (30-137) 20 100** 100** 100**

Nilsson Mechanical Sweden Varied 20 100* 100* 100*

Wennstrom Wedge Sweden Varied 20 100* 100* 100*

Pogonowski Mechanical USA Varied 20 100* 100* 100*

*and ** based on data furnished by proponent *Calculated **Observed

Page 26: SPLICING OF PRECAST PRESTRESSED CONCRETE PILES: PART I ...

Tokyu SpliceTests performed in Japan indicate

that the Tokyu splice is effective insplicing prestressed concrete cylinderpiles. Temperatures due to welding donot heat the concrete as greatly as theNCS splice. It is significant that pre-stressing bars rather than strands areused with the splice because some testfailures have occurred where these barswere threaded at the tips of the bars atthe splice cap.

Raymond Cylinder Pile SpliceThis pile splice was effective in splic-

ing cylinder piles, but not to the sameextent as the NCS or Tokyu splices. Ex-tensive preparations were necessary tosplice the piles. A driving shoe was tackwelded to the bottom section, increas-ing the splicing time somewhat. Theweakness of the splice was in the dow-els and not in the weld.

Bolognesi -Moretto SpliceAnalysis of the Bolognesi-Moretto

splice reveals one possible weakness. Itis felt that the dowels attached to theplates and the weld connecting theplates may cause warping of the plateand damage the splice. An eccentricityis present in the splice. Without furthertest data available, it is difficult to de-termine actual strength levels.

Japanese Bolted SpliceIt is felt that this splice is susceptible

to corrosion because of the large areaof exposed steel. Some protective coat-ing should be used to insure long life ofthe splice and safe performance of thesplice.

Brunspile Connector RingThis splice has performed well in

various load tests. It is felt, however,that it is not a tension splice, and shouldnot be used where tension is expected

in the piles. It is felt that the high levelof field control necessary for the effec-tive performance of this splice is noteasily obtained.

Anderson SpliceOne advantage of the Anderson

splice is that no preparation of the pilesis necessary prior to splicing. Waste ofsplice sections cast with piles is elimi-nated. Piles may be extended easilywhen splicing was not anticipated. Thesplice can be constructed to fit a varietyof pile shapes and sizes. The weaknessof the splice is in the tensile capacity ofthe connection. Extra steps must be tak-en to develop significant tensile re-sistance in the pile. The splice is notpatented.

Fuentes SpliceThis splice has been used successfully

in Puerto Rico for splicing reinforcedconcrete piles. Present design of thesplice restricts the use of the splice tocircular piles. Adapting the splice tech-nique to prestressed concrete piles mayrequire some alterations in the spliceconcept. Presently, the tensile capacityof the splice is obtained by welding thesplice collars to the reinforcing bars.This would be undesirable with the useof prestressing strands.

Hamilton Form Company SpliceIt is felt that cost and time of fabrica-

tion for this splice make it impracticalfor mass production. However, job con-siderations, such as structural perfor-mance and integrity, may warrant theuse of the Hamilton splice in somecases. A patent was not applied for, sothe use of the splice is not restricted.

Macalloy SpliceThough this splice develops struc-

tural capacities virtually the same asthose of an unspliced section, it is feltthat the Macalloy splice is time-con-

PCI Journal/September-October 1974 95

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suming and expensive. Judgment on thepart of the engineer is necessary to de-termine whether the structural effec-tiveness of the splice is more impor-tance than the cost and time aspects.

Mouton SpliceThe fabrication and placing of the

connector sleeves is critical to the per-formance of the splice because the con-nector pin is the only piece which keepsthe sections together. The location ofthe connector pin in the center of thepiles hinders the development of thefull flexural capacity of the pile sectionbecause of the reduced lever arm. Rigidfield control is necessary for the effec-tive performance of this splice.

Raymond Wedge SpliceThe wedges used in this splice are

necessary for the completion and per-formance of the splice. Installation ofthese wedges in the field is critical. Thefit of the sleeves is not as critical withthe use of the wedges.

Pile Coupler Splice

The effective performance of thissplice depends on a proper fit of theconnecting band to the steel plates, andproper anchorage of the steel plates intothe prestressed concrete pile. It is de-sirable that the finished splice be flushwith the longitudinal surfaces of thepile. It is felt that this splice can beutilized effectively and economically,but that more experience in the field isrequired.

Nilsson SpliceAs with other splices utilizing steel

plates, it is imperative that the plates beproperly anchored into the concrete foreffective performance of the splice. Theinterlocking principle requires propertolerances and good field alignment, butonce accomplished, an effective splice

should result. It is essential, of course,that the locking bar remain in positionand not become dislodged.

Wennstrom SpliceThe effective performance of this

splice depends among other things onthe wedges being reliably anchored tothe plate-shaped members. Properalignment of the pile sections is re-quired in order to make the splice. Thewedges must be protected against de-terioration, corrosion, or dislodging; forthe splice would be lost without thewedges.

Pogonowski SpliceIt is felt that the complexities of this

splice demand constant attention andrigorous control in the field. The em-bedding material, introduced in a liquidstate into the void spaces in this splice,must be properly placed if effective cor-rosion control is to be accomplished, forthe hostile environment anticipated.

REFERENCES

1. Britt, G. B., "Rapid Extension ofReinforced and Prestressed Con-crete Piles," Concrete (London),Vol. 5, No. 1, January 1971.

2. Marier, Gaston, "Concrete PileConstruction," U.S. Patent No.3,422,630, January 21, 1969.

3. Severensson, S., AB Scanpile, Let-ter to Robert N. Bruce, Jr., July 6,1972.

4. Stabilator AB, "The ABB Pile Jointfor High Bending Strength," No.624.155, Bromma, Sweden, June15, 1969.

5. Research Committee for the Struc-ture of Joints of Concrete Piles,"The Test Research on the Struc-ture of Joints of Precast ConcretePiles," Reference No. 1/72, Tokyo,Japan, April, 1968.

96

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6. Tokyu Concrete Industry Co., Ltd.,"Experimental Study on StructuralCharacteristics of Joint for TokyuSystems PC Pile," Tokyo, Japan,1968.

7. Bruce, Robert N., Jr., "Cast SteelDriving Splice for 36-in. O.D. Cy-linder Pile," Metairie, Louisiana,August, 1958.

8. Moretto, 0., Bolognesi-MorettoConsulting Engineers, Letter toRobert N. Bruce, Jr., June 8, 1973.

9. Research Committee for the Struc-ture of Joints of Concrete Piles,"The Test Research on the Struc-ture of Joints of Precast ConcretePiles," Reference No. 1/72, Tokyo,Japan, April, 1968.

10. Belden Concrete Products Corpora-tion, "Brunspile," U.S. Patent No.2,983-104, Metairie, Louisiana.

11. Banks, Paul I., Hawaiian Dredgingand Construction Company, Letterto Robert N. Bruce, Jr., July 13,1972.

Company, Inc., Letter to Robert N.Bruce, Jr., August 16, 1972.

14. Goldberg, Donald, Goodkind &O'Dea, Inc., Letter to Robert N.Bruce, Jr., July 25, 1972.

15 Alberdi, T., State of Florida De-partment of Transportation, Letterto Gerald Hanafy, December 1,1971.

1.6 Britt, G. B., "Rapid Extension ofReinforced and Prestressed Con-crete Piles," Concrete (London),Vol. 5, No. 1, January 1971.

17 Andrews, D. A., The Concrete So-ciety, Letter to Robert N. Bruce,Jr., November 13, 1972.

18. Mouton, William J. Jr., "SectionalPile and Coupling Means," U.S.Patent No. 3,651,653, March 28,1972.

19. Fuller, F. M., Raymond Interna-tional, Inc., Letter to Gerald Hana-fy, November 29, 1971.

20 Alley, E. W., "Long PrestressedPiles," Civil Engineering—ASCE,Vol. 40, No. 4, April 1970.ACI Committee 543, "Recommen-dations for Design, Manufacture,and Installation of Concrete Piles,"ACI Journal, Proceedings Vol. 70,No. 8, August 1973.

12. Fuentes, "Fuentes Concrete Pile," 21.U.S. Patent No. 2,698,519 andothers, Bayamon, Puerto Rico,1970.

13. McCalla, W. T., Hamilton Form

Discussion of this paper is invited.Please forward your discussion to PCI Headquartersby February 1, 1975, to permit publication in theMarch-April 1975, PCI JOURNAL.

PCI Journal/September-October 1974 97