Fatigue behaviour of high-strength concrete with respect to strain and stiffness

• Higher frequencies and triangular waveform lead to higher numbers of cycles to failure for high-strength concrete.
• Certain systematologies in influences on strains and stiffness were found.
• Same gradient of strain or stiffness can be reached for different fatigue loading.
• No limit value (strain, stiffness) was found usable for the prediction of fatigue failure.
• The results are encouraging for a more mechanism-orientated approach to fatigue research.

The fatigue behaviour of concrete, and especially of high-strength concrete, has become more important for the design of structures due to more slender structures, which are more sensitive to fatigue loading, or due to wind turbines, which are typically exposed to high-fatigue loading. The fatigue behaviour of a high-strength concrete was investigated within a research project with respect to the influence of maximum stress level, loading frequency and waveform. The investigations were focused on low-cycle-fatigue. The influence on numbers of cycles to failure and on the developments of strain and stiffness were systematically analysed. Selected results are presented in this paper. For the three influences investigated the results show certain systematologies in the change of strain and stiffness parameters with respect to the change in number of cycles to failure.