ABSTRACT
The performance of a concrete component is not constant in the whole life cycle, it will gradually degenerate due to environment attacks and loadings. The development of damages such as crack, abrasion and corrosion, reduces the service life of structures and increases the costs of maintenance and rehabilitation. The structure performance and service life are studied by stochastic analysis. To include all the uncertainties due to the variability in material properties, environment conditions, and loadings, the damage initiation process and propagation process can both be considered as stochastic processes. In this paper, the tremendous amount of uncertainty in the prediction of reliability is considered by combining Poisson process and Gamma process. A lifetime distribution model for concrete components based on these stochastic processes is established. Sensitivity analysis is presented. Influences of parameters on the lifetime distribution were discussed. The parameter analysis results showed that parameters related to the damage development process (Gamma process) control the performance degradation and lifetime distribution. Parameters related to the damage initiation process (Poisson process) were less important. The model presented in this paper can be used to develop optimal maintenance strategies for concrete structures in the life cycle. It also contributes to widening the use of stochastic processes for the modeling of structural degradation processes such as wear, fatigue, crack, corrosion, erosion and so on.
