Abstract:The deterioration of structural performance is a time-variant process with large amounts of uncertainties and incompleteness. It seems to be inevitable that the prediction of the deterioration of the structural performance should be based on a philosophy of information updating. A new system for structural performance prediction is introduced based on Bayesian dynamic models theory. The system aims to incorporate information from any relevant source,leading to amended and updated model structures. Intervention and monitoring techniques are also designed to ensure the stability of the system. A specific structure of Bayesian dynamic model is defined for structural performance prediction. So-called condition indexes are also defined to evaluate the structural performance. Using condition indexes,the deterioration condition of the structural performance can be described by visual inspection information in current engineering practice. Case study illustrates the advantages of Bayesian dynamic prediction. The information updating has favorable effects on reliability analysis and life prediction. The condition indexes are simple and convenient.