Artificial Accelerated Test Method Simulating Chloride Ingress Environment

It is significant to research the durability of reinforced concrete structures, especially that of chloride-induced corrosion in marine environment. Based on the corrosive mechanism and current research situation, an accelerated test method is put forward which simulates environment of Hangzhou Bay Bridge (HZBB).According to the different mechanism of chloride ingression and structural parts of HZBB, the simulation test in laboratory is divided into four parts, such as surbmerged zone, tidal zone, splash zone and atmospheric zone. Every part simulates the corresponding environment to HZBB. After several months, two kinds of experimental data can be gained from the artificial accelerated test and exposure test on site. Firstly, by qualitative analyzing the test data, it is known that the relationship of the surface chloride concentration varying with time and source chloride concentration, as well as the chloride diffusion coefficient of ordinary concrete and marine concrete specimens. Secondly, based on the Fick's second law, different boundary condition and mathematical methods, three calculative models are established and achieved by program. Some conclusions can be made below, one is the relationship between the chloride surface concentration and diffusion coefficient, and another is the influence of temperature upon diffusion coefficient, and the other is some advice found in analyzing similarity of time between different test conditions by the finite difference model. Finally, some suggestions are made by analyzing the influence and sensitive relationship of the surface concentration, temperature, and wetting-drying cycle on the chloride diffusion.The Research is supported by Natural Science Foundation of China (50538070) and HZBB Project Management Bureau.