Experimental analysis of the fatigue life of concrete subject to low cyclic compressive loading

ABSTRACT

The degradation of concrete by fatigue is related to deterioration and damage of the composite material when subjected to cyclic loading. In general, the deterioration of the material subjected to dynamic tests, occurs similarly to that of concretes subjected to static tests, however, the crack propagation mode, the propagation speed and the damage may be different depending on the loading rate at which the material is subjected. Besides, this work presents an experimental investigation aiming to evaluate the influence on the concrete fatigue behavior regarding the loading frequency, load intensity and the material’s compressive strength. Tests were carried out considering three loading frequencies (0.125, 0.25 and 0.5 Hz), two levels of maximum stress (50% and 70% of the compressive strength) and concretes made with three different compressive strength (30, 50 and 70 MPa). The results point out that as the loading frequency is increased, the fatigue life increases exponentially. However, it was observed that the fatigue life is shorter in high-strength concretes, i.e., the fatigue life has an inverse relationship with the compressive strength.

Keywords
Concrete; Cyclic compression; Fatigue; Low cycle fatigue; Fatigue life