No values given

It is impossible to design anchorages on the basis of suitability tests until suitable values are made available in a future revision of the standard.

When the characteristic pull-out resistance Rak is obtained from acceptance tests (see Section 14.4.3), its value is given by:

Ra ,k = Pp where Pp is the measured proof load. 14.5.2 Design pull-out resistance

The design pull-out resistance of an anchorage Ra,d is given by:

Ya where Rak is the anchor's characteristic pull-out resistance and Ya is a partial factor. [EN 1997-1 ยง8.5.2]

Figure 14.4 shows the relative magnitude of actions and resistances used in anchorage design. In this diagram, we assume that the anchor's characteristic external resistance Rak is greater than its internal resistance Rik, given by the tendon's tensile strength Ptk.



Figure 14.4. Hierarchy of parameters in anchorage design

The recommended values of Ya for pre-stressed anchorages are given in Annex A of EN 1997-1 and repeated in the table below. In Design Approaches 1 and 2, Ya = 1.1; and in Design Approach 3, Ya = 1.0 (see Chapter 6 for discussion of the Design Approaches).



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