Cyclic Deterioration of High‐performance Concrete – Findings of the Priority Programme SPP 2020

Modern high‐performance concretes with ever‐higher compressive strengths allow the construction of slender structures which are exposed to higher fatigue‐relevant loads. Current fatigue design rules include a high reduction of the fatigue resistance, which increases with increasing concrete strength. Thus, the fatigue verification becomes crucial for the realisation of such concrete structures. However, there is still a lack of knowledge regarding the damage mechanisms which hinders a substantial improvement of the fatigue design rules. The objective of the priority programme SPP 2020 is to gain more knowledge concerning the fatigue behaviour of high‐performance concretes and damage mechanisms in a strong network of different research institutions. The investigation of the concrete fatigue behaviour is challenging because of the multiple interdependence of influences on the concrete fatigue behaviour, and the damage effects occurring on different scales. Highly instrumented experiments combined with the latest microstructural investigation techniques and numerical modelling on different scales are used to explore the fatigue damage mechanisms. The scope of the priority programme SPP 2020 is outlined and selected results from the projects involved are presented in this paper.