Research On Durability Design Of Concrete Stuctures Exposed To Chloride Enviroment

In this paper, according to the more and more serious problem of durability of concrete structures, based on native and foreign experts' achievements about durability of concrete structures, the elementary theory and achievements are introduced from carbonization of concrete, erosion of chloride ion, alkali-reaction of concrete, freeze-thaw destruction of concrete and reinforcement corrosion, and especially, the mechanism of chloride ion action on steel bar, erosion model of chloride ion and influence factors on chloride ion are analysed and based on them, a new multi-component diffusion equation was deduced, in which the influences of concrete chloride ion binding capacity, time-dependence of chloride diffusivity, . micro-defect of concrete structures and characteristic of concrete were taken into consideration. On this basis a practical model of chloride ion diffusion for concrete service life prediction is obtained. According to this, the thought and method of durability design of concrete structures in the environment of chloride ion, which make the durability design method of concrete structures ameliorated. It calculates the carbonization depth of concrete compared to the concrete cover thickness and provides advice to improve the durability, when drafting the code of durability design of concrete, this paper can serve as a reference.