Abstract: Both the corrosive evaluation criteria of water soil and the protective standards for the durability design of concrete structures are independent and interactive. Through 2groundwater samples, this paper has compared the difference of erosive evaluation criteria of water and soil and protective standard for pile foundation and basement slab by different codes. Generally, the more serious the corrosive environment, the greater the difference of durability design of concrete structure. It is necessary to unify the corrosive evaluation criteria of water and soil and the protective standards for the durability design of concrete structures. In view of the large difference in corrosion evaluation of SO42- and CL-,this paper gives a definition of drying-wetting alternating action and drying-wetting alternating strength, and an unified solution of the erosive evaluation index and classification of water and soil is suggested. Drying-wetting alternating action is defined as a phenomenon of alternating conversion or continuous conversion between liquid phase water and gas phase water on the surface of a solid. Drying-wetting alternating strength is defined as the product of relative evaporation rate of liquid water on the surface of a solid and the saturation of a solid cover.