High-cycle fatigue of notched plain concrete

This paper investigates the accuracy of the so-called Theory of Critical Distances (TCD) in modelling, in the high-cycle fatigue regime, the behaviour of notched plain concrete. The TCD postulates that the fatigue damage extent has to be estimated by directly post-processing the entire linear-elastic stress field damaging the material in the vicinity of the crack initiation locations. According to the TCD's modus operandi, the high-cycle fatigue assessment is performed by using a scale length parameter which is treated as a material property. The accuracy of this method was checked against a number of experimental results generated by testing, under four-point bending, notched specimens of plain concrete. This validation exercise allowed us to prove that the TCD is successful in estimating the high-cycle fatigue strength of notched concrete beams, resulting in predictions falling within an error interval of about ±15%.