Life prediction on protective coating of steel bridge based on gray system theory

The atmospheric corrosion of protective coating of steel bridge is an extraordinary complicated process with many uncertain factors. To build life prediction system of coatings requires using gray system which suits for dealing with the case that contains a lot of uncertain information. The gray system theory is introduced for the study of failure of protective coating of bridge, and a gray model GM (1,1) of coatings corrosion area with variant time is built, a generic predict formula of protective coating life of bridge is put forward based on this theory. Project practices identify that the prediction is in good agreement with field data, and its relative error is less than 8%, so the model has good precision and forecast dependability..