Experimental study of binding chloride ion penetrability in recycled concrete

The engineering characteristics of recycled material made of waste concrete debris after crushing, washing and grading selection, is different from natural bone materials and presents a huge difference in endurance. The migration of dissociative ion in recycled concrete has been initially conducted by few scholars with method of chloride ion electric migration fast test (IIEMFT)^[1-7]. However, it is seldom reported that the penetrability of binding chloride ion is experimented with natural diffusion method of ion in recycled concrete. In practice, the ion transfer is mainly motivated by diffusion and capillary effect, so, it will lead to different results from general cases when IIEMFT is carried out in studying ion penetrability in concrete. It is obvious that the quantity of dissociating chloride ion play a major effect on steel corrosion. There is less dissociating ion left if more ions are combined when the total quantity of ion immigration in the concrete is kept constant. As a result, the rust damage to steel will be minimized. Therefore, it is of paramount significance to study the law of ion distribution in concrete. In this paper, the natural diffusion method is applied in order to systematically study the effect of recycled bone material, dry-wet circulation, fly ash quantity on ion content, which will provide comprehensive basis for the application of recycled concrete in engineering.