Title: Fatigue of Plain Concrete

Author(s): Thomas T. C. Hsu

Publication: Journal Proceedings

Volume: 78

Issue: 4

Appears on pages(s): 292-305

Keywords: compression tests: compressive strength; concretes; cyclic loads; fatigue (materials); fatigue tests, flexural strength; loading rate; strength; stresses.

DOI: 10.14359/6927

Date: 7/1/1981

Abstract:
Fatigue strength of plain concrete is usually presented by the f-N curve (stress versus number of cycles). This curve has recently been extended to include the parameter R, where R is the ratio of minimum stress to maximum stress. This development results in a three-variable f-N-R relationship. This paper presents a more general four-variable f-N-T-R relationship for predicting the fatigue strength of concrete. This relationship incorporates the new dimension of T, which is the period of repetitive loading. Since T represents the rate of loading, and the product of T and N represents the duration of loading, this four-variable relationship simultaneously accounts for the time effect and the effect of loading rate. Based on the f-N-T-R relationship, two equations are proposed for the prediction of fatigue strength of concrete, one for the high-cycle fatigue and one for low-cycle fatigue. These equations have been substantiated by compressive and flexural tests reported in literature.