High-frequency fatigue tests on the shear strength at the unreinforced interface between concretes cast at different times

This article deals with experimental studies concerning fatigue of the interface between concrete cast at different times. The critical view on the adhesive bond in terms of fatigue by the design standards was the motivation for performing fatigue tests on large-scale specimens. For the experimental investigations a method developed at TU Wien was used, which allows high testing frequencies for large specimens. In this method, the specimen is excited in its natural frequency and the fatigue stress is generated by the dynamic forces. The efficiency of this method is based on the minimal time requirement and the low energy consumption compared to the currently applied methods. Two series of experiments were carried out at large-scale test bodies. The results of other performed experimental fatigue tests to bonding between old and new concrete are presented and compared. The requirements of the RVS 15.02.34 [1] to concrete bonding joints and the fatigue analysis for concrete overlays are presented. The subject of this research is used for concrete overlays or concrete road surfaces on bridges.