Monostrand Post-Tensioning System

System Description


The strength, serviceability and design flexibility of concrete are greatly enhanced by the DYWIDAG Monostrand Post-Tensioning System. DYWIDAG Monostrands are made up of cold-drawn, low-relaxation, seven wire strands of 0.5" (12.7 mm) or 0.6" (15.2 mm) diameter, conforming to ASTM A 416. DYWIDAG's small tendon diameters and small anchor plate dimensions meet the edge dimension requirements of slabs as thin as 4-½" (114.3 mm).
All components illustrated are for unbonded construction. Contact your local DSI representative for details for bonded tendon construction or other specialized construction materials.


The DYWIDAG Wedge-Anchor System exceeds ACI Code requirements for guaranteed ultimate capacity of the tendon, and seating losses are reduced to a minimum by the two-piece wedge design. The system meets PTI Guide specifications. Intermediate anchors can be installed at points along the tendon to suit construction joints, and the stressing can be applied at these points. DYWIDAG provides plastic pocket formers as part of standard anchor hardware.

Attached to the formwork for quick positioning of anchors, the pocket formers create small, clean stressing voids that are easily patched. DYWIDAG Monostrand Tendons are assembled at the job site from strand, which is coated and protected by an extruded plastic sheathing. Intermediate and dead end (fixed) anchorages are installed in the plant and stressing anchorages in the field. Wedges for fixed anchorages are hydraulically seated in the plant for positive grip.


DYWIDAG Encapsulated Monostrand System
The DYWIDAG Corrosion Protection System (CPS) offers the design engineer and owner the most dependable and best-engineered post-tensioning corrosion-protection system available today. The anchor in the CPS system is encapsulated in high-density polyethylene thus providing complete protection of the anchor. The anchor is connected to the tendon with a tube providing a positive barrier against penetration into the tendon.


 When the tendon is delivered to site with the dead end anchorage in place, a cap filled with grease is seated into the anchor to ensure a tight seal. After stressing the tendon and burning off the strand extension, a plastic grease filled cap is pushed into the anchor providing a tight seal. A rubber bushing at the end of the plastic tube provides seal against penetration.

 

Assistance
DYWIDAG field technicians are available to assist the general contractor in placing and stressing DYWIDAG supplied tendons where required. Strict compliance with the project's specifications with regard to placing and stressing of the DYWIDAG Tendons must be maintained.

 The grease, extruded sheathing, strand, and anchorages all meet or exceed the PTI Guide Specifications as noted in the Fifth Edition of the Post-Tensioning Manual. With the introduction of this new Corrosion Protection System, DYWIDAG is proud to offer a system believed to be the best available on the market today at competitive prices.

 


Tendons need to be placed to the specific required ordinates of the tendons in order to achieve the structural capacity and the required concrete cover to assure proper corrosion protection for the DYWIDAG tendons.