DYWIDAG Twin-Corr Strand Anchor
Flexible installation with full double corrosion protection (DCP/Twin-Core) for extreme environments.
- Retaining Wall Tieback
- Uplift Restraint
- Excavation Support
The DYWIDAG Strand Anchor System with twin concentric sheathing comprises two corrugated sheaths within the bonded length and individually greased and sheathed strands within the free length, housed within a common external sheath. This system is known as Twin-Core in Europe, but double corrosion protection (DCP) elsewhere.
There is a distinction between the national standards of Europe, UK and America. European Standards tend to accept a single corrugated sheath in the bond length and two plastic sheaths in the free length (strand sheathing within a common external duct) for permanent works in a range of ground conditions. For aggressive environments, European standards typically specify Twin-Core protection. In the UK and other countries using UK specifications, DCP is specified for all permanent works, irrespective of the environment. In America, different grouting systems are used, often pre-grouting the ribbed duct within the bore prior to installation of the tendon bundle, therefore a range of sheathing systems are employed
Concentric ribbed sheathing within the bond length ensures that there are two independent durable barriers between the tendon and the installation environment for enhanced protection
True double corrosion protection (DCP) over the full length of the anchor tendon to comply with national standards and ensure system longevity
Long lengths of up to 90m+ are available to suit multiple applications
Anchors are supplied as single section, and are fully coiled for ease of transportation and site handling
Particularly suited to low headroom or restricted access locations due to the flexibility of the tendon
Anchors can be grouted in-situ or supplied factory pre-grouted, dependent on site restrictions and grouting capabilities
Anchor head componentry can be tailored to specific applications, e.g. re-stressable or de-stressable
Anchor head protection for permanent works comprises specialist anchor protection caps and sealing arrangements to ensure a long service life
Load monitoring options and instrumentation can be incorporated with DYWIDAG Strand Anchor Systems for data-driven insights
Main standards for steel nuances
Europe/ Asia/ Latin America: Steel Strand Ø 15,2mm (0.6 in) and Ø15,7mm (0.62 in) – 1 to 22+ strands
UK: Steel Strand Ø 15,2mm (0.6 in) – 1 to 27+ strands
North America: 7-wire, low relaxation 270 ksi Steel Ø 0.6 in (15,2mm) – 1 to 61 strands
Bearing plates with angle compensation, different finishes, architectural features.
Borehole spacers : lantern or skid
Tremie tubes for borehole grouting (bottom up)
Post-grouting tubes complete with TAM (tube à manchette) valves for bond stress enhancement