Research On The Condition Degeneration Of RC Bridges Considering Spatial Variability

The condition of RC bridges is degenerating quickly in China because of aging of material, increase of traffic, disadvantage environment and lack of maintenance. The life of most RC bridges is 30-40 years. It is much less than the design life. At the same time, the lack of maintenance brought much randomization to the degeneration process. The bridges have a lot of hidden troubles.Many material degeneration models have been developed through test, inspect and investigation in recent years. Research on the condition degeneration of RC bridges is based on these models. Determinate degeneration models were adopted because of the efficiency of calculation in the past. As the development of computer technic, the efficiency of calculation is improved. Random degeneration models were adopted now. Spacial variety has also been considerd in some new research.The research in this paper was based on carbonization models and chloride models. Fistly, the existent models were compared, and some of them were chosen for the research.Distributions of important parameters were studied through bridge inspecting and literature search. These parameters were brought to the models though M-C method. The whole random arithmetic was developed.The spacial variety was considered through spacial elements. The correlation of spacial elements was defined as a correlation coefficient matrix. Many results were calculated following different life rules.The whole degeneration progress of a simple RC beam was simulated basing on the carbonization models and chloride models by M-C method. The influence of spacial correlation to corrosion, crack and probability of fail is studied as a key problem.