Chloride Diffusivity, Fatigue Life, and Service Life Analysis of RC Beams under Chloride Exposure

Abstract

This study investigates the combined actions of flexural fatigue loading and chloride exposure by an experimental examination of the initial fatigue loading cycles (0.2, 0.4, 0.8, and 1.2 million), chloride exposure duration (0, 3, and 6 months), and modeling estimating service life. The results show the following: (1) at the initial fatigue loading cycles of 0.4, 0.8, and 1.2 million, (a) the chloride diffusivity of tensile concrete is similar, which are greater than the specimens initially fatigue loaded with 0.2 million cycles; (b) the chloride diffusivity of compressive concrete increases as the initial fatigue loading cycles increase; and (c) specimens present similar values of fatigue life and service life, which are shorter than the specimens initially fatigue loaded with 0.2 million cycles. (2) As the chloride exposure duration increases from 3 to 6 months, (a) chloride contents of tensile concrete increases more than that of compressive concrete, but both diffusion coefficients decrease; and (b) the fatigue life decreases by ~25%–75% and service life decreases by ~28%–55%. (3) There is an exponential correlation between the fatigue life and service life of beams.