DS CEN/TR 17079:2018

Design of fastenings for use in concrete - Redundant non-structural systems

Scope

1.1 General This Technical Report provides design rules for fasteners used to connect statically indeterminate non-structural light weight systems (e.g. suspended ceilings, pipe work, ducting) to concrete members such as walls or floors (see Figure 1)). The proposed design model may be applied to post-installed mechanical and bonded anchors covered by EN 1992-4:2017.

1.2. Their suitability will be confirmed in a European Technical Product Specification. The design rules assume the following:

- under extreme conditions (e.g. large crack width) excessive slip or failure of a fastener might occur;
- elements or systems are attached with at least three fixing points with one or more fasteners at each fixing point;
- where more than one fastener is used at a fixing point (MF, see Figure 1), only fasteners of the same type, size and length are used;
- the attached system is sufficiently stiff to transfer the load at any fixing point to adjacent fixing points without significantly impairing the performance characteristics of the system both at serviceability and ultimate limit states. (...)

This Technical Report applies to non-structural applications in structures covered by EN 1992-1-1. In applications where special considerations apply, e.g. nuclear power plants or civil defence structures, modifications may be necessary. This document does not cover the design of the fixture. The design of the fixture will be carried out to comply with the appropriate Standards.

1.2 Type of fasteners Post-installed fasteners according to EN 1992-4.

1.3 Fastener dimensions and materials EN 1992-4:2017, 1.3 applies with the following addition:

In precast pre-stressed hollow core elements the minimum embedment depth may be reduced to a value to ensure proper functioning if placed in a flange (wall) of minimum thickness of 17 mm. In this case the minimum embedment depth and the admissible position of the fastener in the hollow core slab given in the relevant European Technical Product Specification will be observed (Figure 2).

1.4 Fastener loading Loading on the fastenings will only be quasi static. Fatigue, impact and seismic loads are not covered. Any axial compression on the fixture will be transmitted to the concrete either without acting on the fastener or via fasteners suitable for resisting compression.

1.5 Concrete strength EN 1992-4 applies.

1.6 Concrete member loading EN 1992-4 applies. However, fatigue, impact and seismic loads are not covered.

1.7 Concrete member dimensions

The minimum thickness of members in which fasteners are installed is at least 80 mm unless otherwise specified in the European
Technical Product Specification. For precast pre-stressed hollow core elements, the minimum wall thickness is 17 mm.