Anwendungsmöglichkeit von Befestigungen in Sicht-Stein-Beton

Application of fastening systems in rock exposing concrete

The approval procedure of post-installed anchors for structural applications is generally regulated in the European Technical Approval Guideline ETAG 001. In this guideline a concrete compressive strength class of C20/25 resp. C50/60 is stated as standard concrete for the required tests. In addition a range for the grain-size distribution curve is given in Annex A of ETAG 001. At large tunnel projects large quantities of excavation material are generated. Due to economic and ecological reasons research is done for using these mineral resources as aggregate for concrete which can be used in the construction of the tunnel itself. At the application of the tunnel equipment post-installed fastening systems will be used and hence the influence on the pull-out capacities has to be considered.
For the evaluation of post-installed fastening systems in a concrete member made of aggregate from tunnel excavation material (Bündnerschiefer from the Brenner Base Tunnel) various fastening systems were tested. The results of the pull-out tests were compared to reference tests which were performed under the same conditions in concrete C20/25.