Tetron Pot Bearings - English

Mechanical pot bearings

TETRON CD®

Mechanical pot bearings

CO N T E N TS

TETRON CD

Tetron CD pot bearings designed and developedby Freyssinet solve structural movement problemsthat occur in particular in civil engineering bridgesand tunnels.Tetron bearings have continued to improve since1960, and the CD range fully satisfies all currentstandards.

CONTENTS:

Function / Description

Technical Specifications

Sizing

Pot Bearing Types

Quality Assurance

Test Benches / Installation

Special Bearings

Some References 1992 - 2002

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Tetron CD pot bearings developed by Freyssinet incorporate confinedelastomer disks. They form the connection between a structure and itssupports.

These bearings have the following advantages:u they resist low to very high vertical loads;u transmission of high vertical and horizontal forces within small overall

dimensions;u high amplitude movement capacity in one or two horizontal directions

with a very low coefficient of friction and without any elastic returnforce;

u high rotation amplitude along any horizontal axis, with a low resistingmoment;

u very high resistance to dynamic loads.

The Tetron CD pot bearing is composed ofan elastomer disk confined in a cylindricalspace limited by a hollow base (the pot)and a piston.Thus the elastomer behaves like an uncom-pressible liquid.

It can thus transmit very high loads andabsorb rotations of the structure.

If the pot bearing is provided with a slidingplate, it becomes multi-directional and aguide can be added to make it single direc-tional.

Thus, there are three available pot bear-ing types:

Tetron CD / FX (fixed)This type consists simply of a pot, a pistonand an elastomer disk.

The Tetron CD / FX pot bearing behaves likea point hinge and can transmit horizontalforces along two directions either by fric-tion to the structures or by anchor devices.

Pot bearings TETRON CD 1

FUNCTION

DESCRIPTION

Vernègues viaduct, Mediterranean TGV line – France

Upper anchor dowel

Sliding plate

Upper attachment screw

Austenitic steel plate

Austenitic steel plate

Retaining screw

Central guide

Sliding material

P.T.F.E. disk

P rotection seal

Piston

Anti-extrusion seal

Elastomer disk

Pot

Lower attachment scre w

Lower anchor dowel

Tetron CD pot bearings are designed to satisfy specifications set down in internationalstandards or any other particular specification.

MaterialsThe source of materials used to make Tetron CD pot bearings is certified to technicalspecifications defined in European standard EN 1337-5 or equivalent.

Protection against corrosionAll metal parts in Tetron CD bearings are protected against corrosion in accordancewith project specifications.This protection may be provided for example by a paint system that may or may notcomplement zinc / aluminum or zinc metallization.

AttachmentsIt may be necessary to fix Tetron CD bearings to the structures using a removable sys-tem, depending on the applied horizontal forces.This attachment is usually made by sockets embedded in the structures onto whichthe bearings are bolted.

OptionsTetron CD bearings may be equipped with the following options on request:u a P.T.F.E. scraper disk protection seal;u a skirt to provide optimum protection against external aggression;u plane or skew external distribution plates;u a movement indicator;u a vertical load measurement device;u temporary equipment for launching bridge deck.

There are other options. Please call a Freyssinet local agent for further information.

Tetron CD / GG (Guided Sliding)This type is a multi-directional bearing provided with a guide.

This guided sliding (or unidirectional) bearing only enables move-m e n t s along the guiding direction.The guidance is achieved either by a central guide fixed on thepiston or the sliding plate, or by side stops fixed to the plate.

The Te t ron CD / GG pot bearing can transmit horizontal forces inthe direction perpendicular to the line of guidance.

TECHNICAL SPECIFICATIONS

2 Pot bearings TETRON CD

Tetron CD / GL (Free Sliding)This type consists of a fixed pot bearing in which the piston is covered by a polytetra-f l u o roethylene (P. T. F.E) disk on which the upper sliding plate fixed to the superstru c t u reis free to move. The bearing constructed in this manner is free to slide (it is multi-direc-tional) and follows displacements in all horizontal directions.The Tetron CD / GL bearing is not designed to transmit horizontal loads.

F reyssinet has developed a complete computer softwarespecifically for pot bearings taking account of the variousapplicable international standards (BS, DIN, AASHTO, EN,Austroads, etc.), the immediate environment of pot bearings( s t ru c t u re types, construction methods, etc.) and selectedoptions, and to satisfy each particular case.

This system comprises a calculation software that includesall parameters that have an influence on the dimensions andcosts of the components and a CAD link that is capable ofautomatically plotting drawings of the bearings thus designed.

Apart from information about applicable standards and theenvironment of bearings, the information necessary for theiroptimum design is shown in the following table given as anexample.

SIZING


Values given for example

COGL1

Concrete

Concrete

23302330

500045002500

00

65003250

00

65003250

00

1050

1050

1050

0.0160.022800

1200110020020

COGG1

Concrete

Concrete

23302330

500045002500500

065003250650

065003250650

0

050

050

050

0.0160.022800

1200110020020

P1FX1

Concrete

Concrete

23302330

20000180001000010002000260001300013002600260001300013002600

0.0160.02210001000

250

P1GG1

Concrete

Concrete

23302330

2000018000100002000

026000130002600

026000130002600

0

030

030

030

0.0160.0221300

12001100300

0

C2GL1

Concrete

Concrete

23302330

500045002500

00

65003250

00

65003250

00

1050

1050

1050

0.0160.022800

1200110020020

C2GG1

Concrete

Concrete

23302330

5000450025005000

650032506500

650032506500

050

050

050

0.0160.022800

1200110020020

Bearing referenceBearing identification (FX, GG, GL)Quantity

Surfaces in contact

Allowable average contactpressure (MPa)

Loads (kN)

Displacement (mm)

Rotation (radians)

Maximum dimensions(mm)

Plate presettings (GG and GL)

Upper surface

Lower surface

Upper surfaceSLS

ULS

SLS

ULS

VerticalMaximum

Permanent

Minimum

Maximum

Minimum

Maximum

Minimum

Transverse

Longitudinal

Vertical

Transverse

Longitudinal

Vertical

Transverse

Longitudinal

IrreversibleTransverse

Transverse

Transverse

Transverse

Transverse

Transverse

Longitudinal

Longitudinal

Longitudinal

Longitudinal

Longitudinal

Longitudinal

Total

Total

Reversible

Irreversible

Reversible

Irreversible

Reversible

Lower surface

Serviceability Limit State

(SLS)

Ultimate Limit State (ULS)

Ultimate Limit State with

earthquake (ULSS)

Serviceability Limit State

(SLS)


Ultimate Limit State with

earthquake (ULSS)

S e rviceability Limit State (SLS)


Pot diameter

Piston diameter (FX)

Plate length (GG and GL)

Plate width (GG and GL)

Total height

Values given for information only

FX 500 - 50

FX 1000 - 100

FX 1500 - 150

FX 2000 - 200

FX 2500 - 250

FX 3000 - 300

FX 3500 - 350

FX 4000 - 400

FX 4500 - 450

FX 5000 - 500

FX 6000 - 500

FX 7000 - 500

FX 8000 - 500

FX 9000 - 500

FX 10000 - 500

FX 12000 - 600

FX 14000 - 700

FX 16000 - 800

FX 18000 - 900

FX 20000 - 1000

FX 24000 - 1200

FX 28000 - 1400

FX 30000 - 1500

FX 35000 - 1750

FX 40000 - 2000

FX 45000 - 2250

FX 50000 - 2500

180

255

295

345

385

420

460

480

510

570

580

620

660

690

730

835

905

945

1000

1095

1190

1260

1305

1415

1515

1610

1700

200

265

320

365

415

450

490

520

560

600

640

670

710

750

795

865

935

997

1055

1125

1220

1320

1375

1475

1585

1680

1770

69

69

78

88

93

97

97

107

117

106

136

145

145

164

163

162

170

190

209

197

216

285

294

312

321

330

368

15

25

40

60

75

95

110

135

170

205

255

305

340

430

470

565

685

865

1085

1135

1475

2400

2670

3280

3865

4415

5620

Designation Ø A (mm) Ø B (mm) C (mm) Weight (kg)

POT BEARING TYPES

We have selected a series of pot bearings for information, to givea rough idea of their dimensions at the preliminary design stage.

The dimensions of bearings calculated according to standard EN1337 are defined in the following tables given for information,for a rotation of 1/100 rad and a maximum concrete stress of 23N/mm2 in the serviceability limit state.In practice, our bearings are designed individually for each caseas a function of standards, particular specifications and actualloads.


Tetron CD/FX Tetron CD/GL Tetron CD/GG

Fixed pot bearing: Tetron CD / FX Designation: FX 12000 – 600

Pot bearing type

Maximum vertical force at serviceability load (kN)

Resultant horizontal force at serviceability load ((kN)



Multidirectional pot bearing: TETRON CD / GL

Unidirectional pot bearing: TETRON CD / GG


GG 500 - 50 - 50GG 1000 - 100 - 50GG 1500 - 150 - 50GG 2000 - 200 - 50GG 2500 - 250 - 50GG 3000 - 300 - 50GG 3500 - 350 - 50GG 4000 - 400 - 50GG 4500 - 450 - 50GG 5000 - 500 - 50GG 6000 - 500 - 50GG 7000 - 500 - 50GG 8000 - 500 - 50GG 9000 - 500 - 50GG 10000 - 500 - 50GG 12000 - 600 - 50GG 14000 - 700 - 50GG 16000 - 800 - 50GG 18000 - 900 - 50GG 20000 - 1000 - 50GG 24000 - 1200 - 50GG 28000 - 1400 - 50GG 30000 - 1500 - 50GG 35000 - 1750 - 50GG 40000 - 2000 - 50GG 45000 - 2250 - 50GG 50000 - 2500 - 50

205

270

325

355

400

430

460

490

520

550

590

620

660

690

730

820

870

935

1000

1050

1160

1255

1300

1410

1510

1605

1695

270

325

365

390

425

445

475

505

535

565

615

660

705

745

785

860

930

995

1055

1110

1215

1315

1360

1470

1570

1665

1755

235

290

330

380

415

440

470

505

535

565

615

660

705

745

785

860

930

995

1055

1110

1215

1315

1360

1470

1570

1665

1755

100

104

104

109

113

118

123

123

137

142

162

162

167

181

185

184

213

242

246

265

284

327

336

365

363

382

410

30

45

60

80

100

120

145

160

200

230

295

350

415

500

560

675

930

1245

1400

1710

2200

2970

3300

4240

4780

5690

6800

Designation Ø A (mm) D (mm) E (mm) C (mm) Weight (kg)

GL 500 - 50 - 20GL 1000 - 50 - 20GL 1500 - 50 - 20GL 2000 - 50 - 20GL 2500 - 50 - 20GL 3000 - 50 - 20GL 3500 - 50 - 20GL 4000 - 50 - 20GL 4500 - 50 - 20GL 5000 - 50 - 20GL 6000 - 50 - 20GL 7000 - 50 - 20GL 8000 - 50 - 20GL 9000 - 50 - 20GL 10000 - 50 - 20GL 12000 - 50 - 20GL 14000 - 50 - 20GL 16000 - 50 - 20GL 18000 - 50 - 20GL 20000 - 50 - 20GL 24000 - 50 - 20GL 28000 - 50 - 20GL 30000 - 50 - 20GL 35000 - 50 - 20GL 40000 - 50 - 20GL 45000 - 50 - 20GL 50000 - 50 - 20

170

225

270

310

345

375

405

435

465

495

545

590

635

680

720

795

860

925

985

1040

1145

1240

1285

1395

1495

1590

1680

245

290

330

370

410

435

460

500

525

555

610

655

695

745

785

855

920

985

1045

1100

1205

1300

1345

1455

1555

1650

1740

225

275

315

355

395

430

465

495

530

550

605

655

695

740

785

860

920

985

1045

1100

1205

1300

1345

1455

1555

1650

1740

90

90

94

99

99

108

108

108

118

112

122

142

157

156

170

169

208

232

244

250

274

293

317

327

356

365

389

25

35

45

60

75

95

110

125

155

175

215

290

275

425

520

595

925

1185

1405

1610

2135

2685

3095

3765

4715

5455

6490

Designation Ø A (mm) D (mm) E (mm) C (mm) Weight (kg)

Designation: GL 12000 - 50 - 20

Pot bearing type


Total longitudinal displacement at serviceability load (mm)

Total transverse displacement at serviceability load (mm)

Designation: GG 12000 - 600 - 50

Pot bearing type



Resultant horizontal force at serviceability load ((kN)

Correct installation of Tetron CD pot bearings is a difficult ope-ration and decisive for durability. Lack of precision or any mis-takes in the various installation steps can introduce forces thatdamage the pot bearings during the life of structures, or eventhreaten the integrity of the structures.There is a specific installation procedure for every project.

The following diagram illustrates the installation of a Tetron CDpot bearing for a cast in situ structure.

INSTALLATION

Tetron CD bearings are made using procedures defined in theQuality Assurance Plan according to ISO 9002. This guaranteesthat they are conform with contractual requirements.

QUALITY ASSURANCE

The quality and operation of Te t ron CD pot bearings are re g u l a r l ychecked by tests according to the different applicable standards(AAHSTO, BS, EN 1337, DIN, etc.) such as:u vertical load;u combined vertical and horizontal loads;u operation with rotation;u wear and friction.

TEST BENCHES


Place the bearing on its support Adjust the bearing Grout the base F o rmwork, re i n f o rcement and pour concrete of the superstru c t u re R e l e a s e

temporary attachments.

1 2 3

4 5

1 2 3

4 5


SPECIAL BEARINGS

The standard Te t ron CD pot bearing is suitable for most applications.H o w e v e r, Freyssinet can design and supply special bearings for speciala p p l i c a t i o n s .

Washington monument inMiami – United States:pot bearing resistant to uplift

Sungai Prai – Malaysia:pot bearing resistant to uplift

Bridge over the Some –Switzerland: pot bearinginstalled on flat jack

Penang bridge – Malaysia:twin pot bearing

TAV – Italy:fixed pot bearing withcontrol horizontal stiffness

CC 601 – Hong Kong:temporary stops

Øresund bridge – Denmark / Sweden:self-centering pot bearing

B e i rut – Syrian bord e r :pot bearing resistant to uplift

C380 Viaduct – Taiwan:pot bearings for very highhorizontal seismic loads

9

1 2

3 4

5 6

7 8

1

7

2

6

8

3

4

9

5

8 Mechanical bearings TETRON CD

SOME REFERENCES1992 – 1997

1992 – FranceTours Palais des Congrès

14 pot bearings

1996 – Taiwanviaduct C 301

100 pot bearings

1996 – FranceVernègues viaduct

56 pot bearings

1997 – FranceLe Corbusier

Euralille bridge3 pot bearings

1997 – PortugalVasco de Gama bridge

160 pot bearings

1997 – FranceCrozet viaduct

94 pot bearings

1994 – Hong KongKwai Chung viaduct784 pot bearings

1993 – PortugalLoures viaduct

148 pot bearings

1996 – BrazilLinha Amarela viaduct

88 pot bearings

1996 – FranceVentabren viaduct

80 pot bearings

1998 – KoreaSeohae bridge

48 pot bearings

2000 – TurkeyAtaturk stadium2 pot bearings

1998 – MalaysiaSungai Dinding bridge

48 pot bearings

1999 – FranceDordogne viaduct36 pot bearings

2001 – MalaysiaPutra Jaya bridge12 pot bearings

2002 – TaiwanRailway viaducts4000 pot bearings

1998 – FranceBeaucaire bridge8 pot bearings

2002 – FranceSomain bridge8 pot bearings

1999 – SpainTAV viaducts

256 pot bearings

SOME REFERENCES1998 – 2002

1 bis, rue du Petit-ClamartB.P. 135 - 78148 Vélizy Cedex - France

Tel.: +33 (1) 46 01 84 84Fax: +33 (1) 46 01 85 85

www.freyssinet.com

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Tetron Pot Bearings - English