Cyclic cumulative damaging of reinforced concrete in post-peak regions

Abstract

Repetition of higher stresses apparently causes progressive damage, which is also strain/stress rate-dependent. This paper aims to separate time-dependent cumulative nolinearity and the effect of repetition of strain path on the overall damage evolution of concrete in compression. Cyclic uniaxial compression tests of concrete were conducted and time-dependent plasticity and stiffness degradation were subtracted from total stress-strain relations to purely extract the effect of repeated stress cycle. Coupling of time dependency and authentic cyclic accumulation of damage was examined by both material and structural experiments especially in post-peak regions, and its applicability was experimentally verified mainly under low cyclic (N<100) actions. The high cycle (N>100) fatigue life predicted by the proposed constitutive law was also verified in terms of the S-N curve.