Unbonded External Post-tensioning

DYWIDAG external unbonded post-tensioning systems strengthen wide-span bridges and wind towers.

DYWIDAG external post-tensioning systems use tendons with strands and wires—or DYWIDAG Threadbars™.

External unbonded post-tensioning systems are used in

External strands and wires : Typical applications for external tendons with strands and wires include bridge construction, where they are used as longitudinal tendons between bulkheads, and in the pre-stressing of concrete and hybrid wind towers, where they are used as vertical tendons.  External mono-strands: Special applications for external mono-strands include round tank walls. The tendons form a closed ring arranged in either a circular or semicircular pattern. A circular arrangement is also possible using a single-strand floating coupler.

External DYWIDAG bars: A significant field of application here is in increasing the shear capacity of structures where bar tendons are arranged vertically outside webs—to replace any missing stirrup reinforcement.

Strand systems up to 55 strands and monostrand systems

Bar systems up to diameters 47mm

Wires systems up to 84 wires

Corrosion protection with flexible fillers contributes to the structural durability

Low induced stress range 

Less fretting fatigue 

Monitoring of stressing forces 

Restressing possible, if required 

Inspectable and replaceable 

Deviation solutions available

Prefabrication resp. site assembly possible