LIFE PREDICTION OF CONCRETE STRUCTURES AFTER ELECTROCHEMICAL CHLORIDE EXTRACTION

摘要

Electrochemical chloride extraction (ECE) test of cylinder RC specimens have been made with different extraction duration, 4 weeks, 6 weeks and 8 weeks respectively. After ECE treatment, the ions profile in concrete has been studied. Study has shown that ECE can remarkably reduce the chloride concentration in concrete and change the profile of the chloride ions, but also increase the OH" concentration nearby the steel bars. Hence the improvement of the ECE method to concrete durability depends on both chloride extraction and OH- concentration. Nevertheless the ECE can change the chloride diffusion coefficient. Tests have shown that after ECE, the chloride diffusion coefficient of concrete is lesser than that of the original one. In order to made the life prediction of concrete structures treated by ECE, the chloride and OH- profile, the chloride diffusion coefficient after ECE must be take into consideration. In this paper, the life prediction of concrete structures treated by ECE has been made.