Fatigue Behavior of High‐Performance Concrete

Abstract

A fatigue study was performed on two commercial high‐strength concretes of 70 MPa and 95 MPa with water/cementitious material ratios of 0.28 and 0.23, respectively. Specimens were cast at the construction site and cured in the laboratory. Tests were performed under constant amplitude, and strains were measured continuously using strain gauges. The McCall model for fatigue life prediction was found to be satisfactory, and safer than the usual Wöhler curves. Strain evolution and stiffness degradation with the number of cycles in high‐strength concrete were found to be similar to those of normal concrete. Strain at failure under cyclic loading was found to be of the same order as the strain at peak load under static loading. Interesting correlations between strain rate and number of cycles to failure and between stiffness decrease rate and number of cycles to failure were found. Evolution of the hysteresis loop was studied. Energy dissipated was found to decrease after the first cycles, and increased steadily thereafter up to failure. Finally, the differences in deformation characteristics between the two high‐strength concretes studied in this investigation were analyzed.