Chloride Penetration in Concrete under Coupled Hygromechanical Loadings

摘要

A novel concrete specimen was designed to facilitate the simultaneous action of mechanical loading and chloride penetration through concrete. The chloride penetration is evaluated by concentration profile in concrete specimens. The damages of concrete due to mechanical loading were characterized in two aspects: the applied loading level and loading repetition and the internal damage measured by travel time of ultrasonic signals. The test results of concentration profiles showed that with increasing loading level from zero up to 70% of compressive strength of concrete, both chloride concentration and penetration depth increased. The most drastic increase occurred in the loading range above 60% of compressive strength. The test results from ultrasonic tests are consistent with the analysis on concentration profile. This means that cyclic loading (low cycles) accelerates chloride penetration through concrete when the loading level is above 60% of the concrete strength.