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  • Freyssinet HDStay cables

  • Freyssinet stay cable technology was first developed in the

    mid-1970s, and has been improved continuously ever since.

    It is the reference in terms of fatigue resistance, protection

    against corrosion, inspectability and replaceability.

    Freyssinet HD stay cables

    3

    4

    6

    8

    10

    11

    The inventor

    of the multistrand

    stay cable

    The Freyssinet

    anchorage

    Options

    Aerodynamic

    stability

    Installation

    Some references

    contents

  • The inventor of the multistrand stay cable

    3

    A parallel strand system: robust and flexible

    Freyssinet invented the multistrand parallel system in 1976. The Freyssinet HD stay

    cable is based on each strand being completely independent.

    This principle has many advantages, including:

    installation and tensioning of each strand individually;

    individual protection against corrosion;

    individual removal and replacement if necessary.

    The standard range of HD stay cables varies from 1 to 169 strands. However, there

    is no limit to the capacity or the length of stay cables. The largest stay cables yet

    installed were for the Collserola telecommunications tower in Spain (205-strands)

    and the longest are the stabilization stay cables for Ting Kau bridge in Hong Kong

    (465 m long).

    The Freyssinet monostrandA galvanised strand with a semi-bonded sheath

    The tension element of the Freyssinet HD stay cable consists of a group of parallel

    individually protected T15.7 strands named Freyssinet monostrand.

    This patented stay cable strand has excellent durability and provides perfect protection

    against corrosion due to two complementary nested barriers formed by galvanisation

    and a semi-bonded individual HDPE sheath extruded onto the strand after the inter-

    stices have been filled with a specifically developed wax.

    The bundle of Freyssinet monostrands is usually contained in an HDPE (High Density

    Polyethylene) co-extruded outer pipe specially designed to satisfy stay cable needs

    and to give excellent durability.

    Collserola tower / SpainTing Kau bridge / Hong Kong

  • Bending filtration, high fatigue and corrosion resistance

    The Freyssinet HD anchor is the most compact stay cable system. It performs all functionsrequired for a stay cable:

    protection against corrosion at unsheathed ends of the strands using a pat-

    ented stuffing box provided with the latest developments in waterproofing;

    resistance to axial fatigue, largely due to the Freyssinet wedges specially

    designed to resist 300 MPa stress amplitude at 45% of ultimate strength

    for 2 million cycles;

    resistance to bending fatigue using a filtering guide/stuffing box

    device capable of filtering radial forces;

    very easy individual installation and adjustment of strand forces. This particular

    arrangement also enables monitoring of cables by replacing a test strand

    at regular intervals.

    The Freyssinet anchorage

    4

    BOTTOMfixed anchorage

    D

    JF

    eH

    (HFxHF)hole IF{bearing plate

    formworktube

    antivandalismtube

    C = (BF or BR) + 66depending on type of anchoragecap

    block

    BF x eBF HDPE sheath

    GxeG

    LFo 80 L min.

    cap

    variable strandoverlength

    special stay cable wedges (patented)

    anchorage block surface corrosion protected - externally

    threaded on adjustable anchorage

    steel anchorage tube

    soft corrosion protection materialoptimising fatigue resistance

    stuffing box / strand guideassembly (patented)

  • 5TOPadjustable anchorage

    Strand stay cable fatigue test(LCPC, Nantes, France)

    (HRxHR)hole IR{bearing plate cap E JRgathering collar formwork tube BR x eBR nuteH

    LRoL min.

    Type

    12

    19

    27

    31

    37

    48

    55

    61

    75

    91

    109

    127

    169

    BF

    177.8

    219.1

    244.5

    244.5

    273

    323,9

    323.9

    355.6

    368

    419

    431.8

    457.2

    530

    Formwork tube Flange/Nut Outer pipe Bearing plate* Cap Gatheringcollar

    eBF

    6.3

    6.3

    6.3

    6.3

    6.3

    8

    8

    8.8

    8.8

    10

    10

    10

    12.5

    BR

    219.1

    244.5

    298.5

    298.5

    323.9

    368

    368

    406.4

    445

    482.6

    530

    558.8

    635

    eBR

    6.3

    6.3

    8

    8

    8

    8

    8

    8.8

    10

    11

    12.5

    12.5

    12.5

    D

    210

    250

    280

    290

    320

    356

    370

    405

    433

    480

    500

    545

    625

    E

    235

    284

    336

    346

    368

    415

    438

    460

    506

    546

    600

    640

    740

    G

    125

    140

    160

    160

    180

    200

    200

    225

    250

    280

    315

    315

    355

    eG

    6

    6

    6

    6

    6

    6,2

    6.2

    6.9

    7.7

    8.6

    9.7

    9.7

    10.9

    HF

    275

    340

    400

    420

    460

    520

    550

    600

    640

    720

    770

    810

    950

    HR

    300

    350

    420

    440

    470

    540

    570

    610

    670

    750

    815

    850

    980

    eH*

    50

    50

    60

    60

    70

    80

    80

    90

    100

    110

    120

    130

    140

    IF

    151

    186

    212

    221

    239

    273

    285

    318

    342

    374

    386

    424

    490

    IR

    192

    230

    260

    270

    290

    330

    350

    375

    405

    450

    480

    525

    605

    JF

    200

    240

    270

    280

    300

    345

    360

    395

    423

    470

    490

    535

    615

    JR

    160

    194

    222

    233

    252

    291

    304

    336

    368

    410

    435

    478

    555

    LFo

    275

    275

    285

    290

    305

    315

    320

    330

    340

    360

    380

    400

    430

    LRo

    346

    356

    376

    386

    411

    434

    446

    466

    481

    524

    560

    600

    660

    L min

    1 200

    1 400

    1 750

    1 750

    1 900

    2 100

    2 200

    2 400

    2 500

    2 850

    3 100

    3 250

    3 700

    Dimensions in mm. * The bearing plate dimensions shown above correspond to concrete structure with 28 days 36 MPa.For steel structures, plan dimensions are valid as minimum, thickness eH is to be designed.

    It is recommended that each stay cable should have a fixed

    anchor at one end and an adjustable anchor at the other.

    Fixed and adjustable anchors can be installed in the tower or in

    the deck indifferently and may or may not be the stressing end.

    Anchors are designed to provide optimum mechanical perfor-

    mance that results in a very high fatigue limit and residual breaking

    strength after fatigue.

    All components forming part of the Freyssinet HD anchorage

    system have been intensively tested in independent laboratories,

    and the results have exceeded the main international acceptance

    criteria (over 95% of ultimate after fatigue testing).

    The Freyssinet anchorage has been qualified according to latest

    PTI and CIP standards.

  • 6resund bridgeDenmark-Sweden

    Options

    Freyssinet offers a wide choice of solutions to satisfy all functional and aestheticconsiderations.

    Cohestrand: cables for very aggressive environment

    The Freyssinet HD stay cable can be adapted to provide better anti-corrosion

    performance for specific environments, by replacing Freyssinet Monostrand by

    Cohestrand strand.

    This is a sheathed strand with seven galvanised or galfanised (coating composed

    of a 95% zinc and 5% aluminum alloy) steel wires, covered by a system capable

    of resisting corrosion in very corrosive environments and also taking axial loads

    through the sheath when required.

    Freyssinet outer sheath: outstanding durability

    Intensive research has led to a range of durable outer sheaths.

    The outer sheath is composed of two layers of co-extruded HDPE: an inner black layer

    and an outer coloured layer.

    Tests have been carried out on all Freyssinet coloured sheaths to verify long term

    colour stability. Close control during manufacturing guarantees a durability three times

    longer than commercially available black and coloured polyethylene, for resistance to

    ultra-violet induced oxidation and stress cracking.

    A special HDPE sheath has also been developed with a silver coloured in-depth

    metallized outer layer that resembles a brushed stainless steel sheath, while main-

    taining the ease of placement of HDPE sheaths and the presence of the helical rib

    aerodynamic protection.

    For any location in the world, Freyssinet can provide justification of sheath durability.

    Compact sheath

    For large cable-stayed bridges with a span in excess of 400 m, the drag of the

    wind on the cables generates significant stresses on the pylon. In order to reduce

    this stress, and to meet design requirements, Freyssinet has developed a compact

    outer stay pipe that reduces the space between the bundle of strands and the pipe

    to a minimum. The durability of this pipe is identical to the standard pipe.

    RAL 9003

    RAL 7035

    RAL 5024

    RAL 5018

    RAL 1016

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