International Catalogue

Basic Knowledge of Fastening Technology
Basic Knowledge of Fastening Technology
Approval specifications
for fixings
Currently, according to the above-mentioned ETAG 001, Parts 1-6, approvals
for metal fixings in concrete are possible for:
▪Torque-controlled expansion anchors
▪ Undercut anchors
▪ Deformation-controlled expansion anchors
▪ Bonded anchors
▪ Anchors for multiple use for non-structural applications
The resulting approvals still contain only the characteristic values of the respective fixing
type. Using the design resistance guidelines (ETAG 001, Annex C for steel anchors and
TR029 for bonded anchors) and the characteristic values for the load bearing capacity of
the respective fixing type, it is possible to design any anchoring. Three design methods
(A, B and C) are available depending on the respective fixing type.
The ETAG 001 divides possible approvals of metal fixings in 12 options. Options 1-6
are for use in cracked and non-cracked concrete, options 7-12 are only for use in noncracked
concrete. Approvals according to Option 1 give the most flexibility of the fixing
connections, those according to option 12 are most restricted. That means fixings with
approvals according to option 1 are of the highest value and the value according to
option 12 is the lowest. It is possible to optimally utilise anchorings because of the type
and manner of design and the division of the approvals into different options.
Part 6 of the ETAG 001 regulates the use of metal fixings in cracked and uncracked
concrete that are used as multiple fixings of non-load-bearing systems. Non-load-bearing
systems include components that do not contribute to the stability of the construction.
These are for instance simple suspended ceilings and underceilings, pipelines as well as
facade claddings. These systems can be referred to as so-called redundant systems. In
case of failure of a fixing point, the stability of the system is not affected.
For the use of anchors for multiple fixings, it is assumed that in case of excessive slip or
failure of a fixing point, the load is transferred to a neighbouring fixing point (without
essential deviation of the requirements regarding the serviceability and the limit state of
the load bearing capacity at the component to be fixed). Here, a fixing point can consist
of one or more anchors.
Calculation of fastenings
According to ETAG 001, the effort for designing of anchorings by designers and users
is relatively high, since evidence has to be given of various failure modes.
The design method in ETAG 001 is based on the CC method of the DIBt from the
year 1993. It is based on the concept of partial safety factors.
With the method A already mentioned above, the characteristic resistances depend on
the load direction and take into consideration all conceivable failure modes (see
Failure Modes chapter).
With method B, a characteristic resistance is assumed to be independent of the load
direction and the influence of reduced edge distances and spacings are taken into
consideration with factors. In principle, this method corresponds to the κ-method in the
older approvals..
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