1978. Report on prestressing steel: 2. Anchorage and application of pretensioned 7-wire strands

This document is one of a series of reports written by members of the Commission on Prestressing Steels and Systems, who for this purpose work together in small ad hoc committees.

This report was prepared by Mr. A. J. Chr. Dekker of the Netherlands, as reporter of the ad hoc Commission on bond problems.

Within the Commission, it was considered necessary to study the bond of prestressing steel used in pretensioned prestressed concrete. This is because there is a relationship between the recommendations written for the anchorage of post-tensioned prestressed concrete and the anchorage by bond of groups of wires or tendons in pretensioned prestressed concrete.

Of course, there are also differences between the two types of anchorage, especially because bonded prestressing steel interacts with the structural behaviour.

This report therefore deals with structural problems such as shear resistance at beam ends, support conditions, stresses, forces, and the required reinforcement in pretensioned beam ends. It provides, in essence, guidelines for practical construction and can serve as a basis for FIP recommendations.

In this first edition, particular attention is paid to the anchorage of 7-wire strands, since this type of prestressing steel is widely used in pretensioned prestressed concrete.

Finally, on behalf of the Commission, I would like to thank Mr. Dekker and the other members of the ad hoc Commission on bond problems for their work and for the dedication they have shown to the advancement of prestressed concrete through the preparation of this report.