Corrosion protection is key in the durability of cable structures

The monostrand technology:
full corrosion barrier and high fatigue resistance

Monostrand

One of the most important move in this area is the development of the Monostrand technology -for individually protected strands, that was carried out by Freyssinet at the end of the eighties and installed on a few bridges as soon as 1988. The objective was to get a protection that is durable, flexible enough to accommodate deformation and elongations and that can connect to the anchorage in a proper way.

Several years of R&D lead to the industrial development of the wax and HDPE (High Density Polyethylene) sheathed semi-bonded mono-strand for which the sheathing is semi-bonded to the steel strands thanks to a qualified amount of wax. The HDPE sheathing is tight enough on the strand so that thermal expansion is the same for both materials.

Key advantages

01. High corrosion protection

Triple barrier corrosion protection: the strands are galvanised, waxed and coated with HDPE.

02. Redundancy

Each strand is individually protected and anchored, which provides a high level of performance and durability.

03. Modularity

The number of strands is adjusted to the required force in the cable.

04. High durability

Improved service life, thanks to the proven endurance of the Monostrand system.

05. Optimized design

Steel grade up to 2160 Mpa strand for reduced cable size.

06. Longest track record

The first major reference for Monostrand system was the Normandy Bridge in France, which paved the way for modern stay cable technology.

07. A solution for each project

Monostrand systems are tailored to meet all your needs, from long-span cable-stayed bridges to suspension bridges.

08. Easy maintenance

Possible replacement of a partial cable section.

Cable systems: our range of strand technologies

Monostrand® technology

The strands are galvanized, waxed and individually sheathed with a continuous wear resistant HDPE sheathing, providing each strand with a triple protection system. The system is suitable for 1860 and 2160 MPa steel grades, and compliant with all national and international standards. A compact version is available for specific project requirements, whenever the wind fairing surface of the cable layers should be reduced. Applications: cable-stayed bridges, suspension bridges, extradosed bridges, stadiums.
  • Individual tensile elements for redundancy
  • Individual corrosion protection system,
    triple corrosion barrier
  • Cable force preserved,
    no cable elongation after initial tensioning

Cohestrand® technology

The specificity of the Cohestrand technology is the co-extrusion of a proprietary bonding resin and polyethylene onto the strand, with precise control of the extrusion parameters to achieve a sufficient bond. This process is carried out at Freyssinet’s production sites and is subject to strict quality control. The minimum shear resistance of the compound, between the outer sheath and the seven-wire strand, is 4 MPa at 20°C. This method ensures that the triple barrier strand protection is of industrial quality, consistency and reliability.
In order to reduce the cost of the technology, a specific Locally Cohesive Strand (LCS) has been developed for extradosed bridges. Applications: cable-stayed bridges, suspension bridges, extradosed bridges.
  • Full locking of sliding force
  • Continuity and redundancy of corrosion protection
    through pylon saddles or suspension collars
  • Cable force preserved,
    no cable elongation after initial tensioning

Carbon Fiber Reinforced Polymer strand

The Carbon Fiber Reinforced Polymer (CFRP) is an advanced composite material with the following advantages: high strength, light weight, no corrosion and excellent fatigue resistance.
Unidirectional CFRP can hence be used as an alternative to steel cables when the total weight of the cabled structure needs to be reduced. Applications: cable-stayed bridges, stadiums.
  • Flexible cable installation and replacement
  • Inert to corrosion mechanisms
  • Cable force preserved,
    no cable elongation after initial tensioning

Monostrand® technology

The strands are galvanized, waxed and individually sheathed with a continuous wear resistant HDPE sheathing, providing each strand with a triple protection system. The system is suitable for 1860 and 2160 MPa steel grades, and compliant with all national and international standards. A compact version is available for specific project requirements, whenever the wind fairing surface of the cable layers should be reduced. Applications: cable-stayed bridges, suspension bridges, extradosed bridges, stadiums.
  • Individual tensile elements for redundancy
  • Individual corrosion protection system,
    triple corrosion barrier
  • Cable force preserved,
    no cable elongation after initial tensioning

Cohestrand® technology

The specificity of the Cohestrand technology is the co-extrusion of a proprietary bonding resin and polyethylene onto the strand, with precise control of the extrusion parameters to achieve a sufficient bond. This process is carried out at Freyssinet’s production sites and is subject to strict quality control. The minimum shear resistance of the compound, between the outer sheath and the seven-wire strand, is 4 MPa at 20°C. This method ensures that the triple barrier strand protection is of industrial quality, consistency and reliability.
In order to reduce the cost of the technology, a specific Locally Cohesive Strand (LCS) has been developed for extradosed bridges. Applications: cable-stayed bridges, suspension bridges, extradosed bridges.
  • Full locking of sliding force
  • Continuity and redundancy of corrosion protection
    through pylon saddles or suspension collars
  • Cable force preserved,
    no cable elongation after initial tensioning

Carbon Fiber Reinforced Polymer strand

The Carbon Fiber Reinforced Polymer (CFRP) is an advanced composite material with the following advantages: high strength, light weight, no corrosion and excellent fatigue resistance.
Unidirectional CFRP can hence be used as an alternative to steel cables when the total weight of the cabled structure needs to be reduced. Applications: cable-stayed bridges, stadiums.
  • Flexible cable installation and replacement
  • Inert to corrosion mechanisms
  • Cable force preserved,
    no cable elongation after initial tensioning

Strands technologies

Download our technical datasheets
Documentation
Documentation

Our references for cable systems

Build
Russia

Russky Island cable-stayed bridge

Russky Island cable-stayed bridge pushed the limit for cable-stayed structures, its main span setting a new world record and demanding extra-long cables designed for the region’s harsh climate.
Discover more
New build
South Korea

Saemangeum bridge’s ultra-strong cables

A South Korean initiative to support new innovation has prompted the development of ultra-high-strength wire for parallel strand cables being installed on a cable-stayed bridge on the west coast.
Discover more
Build
Vietnam

An Dong bridge’s multihole saddle

The latest generation of Freyssinet’s multihole saddle, which offers improved performance and durability, was used for the first time on Vietnam’s An Dong extradosed bridge.
Discover more
Build
Vietnam

Cua Dai extradosed bridge using Cohestrand technology

Locally-cohesive Cohestrand technology was successfully produced and installed for the first time on an extradosed highway bridge which crosses the Tra Khuc River to create a coastal bypass of Quang Ngai city.
Discover more
Build
Turkey

Sultan Yavuz Selim, the hybrid bridge

The third Bosphorus crossing pushed stay cable technology to the next level, combining a traditional suspension system with high-strength cables to stabilise the bridge and future-proof it for trains.
Discover more
Kumhokang bridge, South Korea
Laroin bridge / Carbon fiber strand and Pylon anchorage
Laroin footbridge, France
New Dehli stadium roof
Perene bridge, Peru / Cohestrand and Multihole saddle
Verdun-sur-Garonne bridge, France
An Dong extradosed bridge, Vietnam
Calli extradosed bridge, Turkey
Ewijk bridge, Netherlands
Geum-Ho bridge, South Korea

Other cable system solutions

Anchorage solutions

Anchorages are engineered by Freyssinet internal design team to extend the life of stay cables. They are also manufactured in-house to ensure the highest level of manufacturing control. Our modular solutions cover all needs from short cable hangers using clevis up to very long span cables.

Damper solutions

Dampers are mechanical assemblies installed between the cable and the bridge. They dissipate energy to ensure the stability of the cable.

Cable protection solutions

In addition to the risks associated with the construction of a bridge, owners must consider the risks throughout the life of the bridge, such as fire, lightning, explosion or ice formation on cables. We have developed specific solutions for those of you who wish to better control these risks and limit or avoid the closure of a bridge and its impact on the local economy.

Aesthetic enhancement solutions

Cable-stayed bridges are elegant and strong structures that can become iconic architectural landmarks. To further enhance their aesthetics, we have developed coloured ducts and lighting systems. Combining functionality, aesthetics and mechanical performance, our solutions are customised to your requirements.

Suspension cable solutions

The parallel strand system developed by Freyssinet, well known for cable-stayed bridges and extradosed bridges, brings advantages in terms of durability for suspension bridges and cabled stadium roofs.

Cable systems

Cabled bridges and structures are sustainable, environmentally friendly and architecturally outstanding structures.

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