Bonded Strand Post-Tensioning System, Spain, La Coruña: The Museum of Man

Bonded Strand Post-Tensioning System

System Description

DYWIDAG Post-Tensioning Systems are renowned for reliability and performance, most suitable for all applications in post-tensioned construction. They embrace the whole spectrum from bridge construction and buildings, to civil applications, above and below ground.

 

The first ever structure built with a prototype DYWIDAG Post-Tensioning System using Bars was the arch-bridge Alsleben (Germany) in 1927. From that time on, DYWIDAG has continuously improved its systems to keep up with the growing demand of modern construction technology. In addition to the traditional post-tensioning system using bars that is mainly geared towards geotechnical applications, building rehabilitation and strengthening, DSI offers a complete product line in strand post-tensioning (bonded, unbonded and external) as well as stay-cables and is thus able to fully serve the post-tensioning market. DYWIDAG Post-Tensioning Systems have always combined highest safety and reliability standards with most economical efficiency in their research and development.

Dependable corrosion protection methods of the DYWIDAG Post-Tensioning Systems contribute to the longevity of modern construction. High fatigue resistance is achieved by optimized material selection and cautious detailing of all the components, especially in their system assembly.

We look back on many years of valuable experience in the field of post-tensioning, which leads to our extremely versatile product range that offers economical solutions for practically any problem. This includes our highly developed, sophisticated equipment which is easy to operate in all phases beginning with assembly, installation, stressing and grouting. DYWIDAG Post-Tensioning Systems are being developed and maintained by DYWIDAG-Systems International and are serviced and distributed by a worldwide network of subsidiaries.

Our systems comply with the international specifications and recommendations (ASTM, AASHTO, BS, Eurocode, DIN, Austrian Code, SIA, FIP, fib, EOTA, etc.). The American construction market has a specific product range that is described in separate brochures.

The quality of the DSI products and services is in full compliance with ISO 9001.

DSI Scope of Services:

  • consulting
  • design and shop-drawing engineering
  • manufacturing and supply
  • installation or training and/or supervision of installation
  • inspection and maintenance

Post-Tensioning System using Strand

Strands are made from 7 individual cold-drawn wires, 6 helically wound outer wires and one center wire (king wire). The mechanical properties of the strand as well as corrosion protection properties are most important to DSI.

Strands can be supplied either bare, galvanized or epoxy-coated without any loss in strength including the wedge anchorage. For a maximum in corrosion protection we offer electrically isolated systems using polyethylene (PE) or polypropylene (PP) ducts.

 

DSI Post-Tensioning Anchorage - construction joint

D - drain   V - vent   G - grout injection   C - coupler   S - stressing anchorage   P - post-grouting injection

code / specification 13mm (0.5") 15mm (0.6")
type ASTM A416 prEN 10138 ASTM A416 prEN 10138 ASTM A416 prEN 10138
  Grade 270 BS 5896 Super Grade 250 BS 5896 Super Grade 270 BS 5896 Super
yield strength f p0.1k (N/mm 2 ) 1,670 1 1,640 2 1,550 1 1,560 2 1,670 1 1,640 2
ultimate strength f pk (N/mm 2 ) 1,860 1,860 1,725 1,770 1,860 1,860
nom. diameter (mm) 12.70 12.90 15.20 15.70 15.24 15.70
cross-sectional area (mm 2 ) 98.71 100.00 139.40 150.00 140.00 150.00
weight (kg/m) 0.775 0.785 1.094 1.180 1.102 1.18
ultimate load (kN) 183.7 186.0 240.2 265.5 260.7 279.0
modulus of elasticity (N/mm 2 ) ~195,000
relaxation 3 after 1,000 h
at 0.7 x f pk 		(%) max. 2.5

In addition to standard strands, DSI offers a variety of special strands such as DYFORM with a guaranteed ultimate capacity of 300 kN. The technical data for these products is available upon request.

1) yield measured at 1% effective elongation

2) yield measured at 0.1% residual elongation 3 ) applicable for relaxation class 2 according to Eurocode prEN 10138/BS 5896: or low relaxation complying with ASTM A 416, respectively.