ABSTRACT
Shanghai Subway belongs to the Fast OrbitTransportation System in the city. Because of such characteristics as being free from weather influence and being safe and fast, it becomes the key vehicle within network of the passenger transportation (Shen et al. 1998). The subway structure is a permanent concrete structure, so the investment is usually huge, and it always crosses key districts of city. The requirement of durability of subway is higher than that of other engineering (the base period for design is 100 years), and the problem of durability is of most urgency.
