Fatigue behaviour and damage accumulation in RAC subjected to cyclic compressive loadings

In this paper a constitutive modelling developed by the authors for Natural Aggregate Concrete (NAC) is used to investigate the fatigue behaviour of Recycled Aggregate Concrete (RAC) subjected to compressive constant and variable amplitude stress cycles. The constitutive modelling takes into account the non-linear damage accumulation occurring in the material by using the stress-strain envelope concept. The identification of the parameters that define the constitutive modelling for RAC has been carried out through calibration with the available experimental data found in the literature. The present investigation allows to set up a predictive model that can be used to estimate the fatigue performance of RAC elements taking into account the compressive strength fc′, the replacement percentage of coarse natural aggregates with recycled ones ρ and the concrete mix type. Finally, a comparison between the fatigue experimental data and the provisions of the fib Model Code is carried out.