Evaluating rating factor for prestressed concrete girder bridges by nonlinear finite element analysis

摘要

This study provides a new approach to evaluate the load carrying capacity in rating factor (RF) of prestressed concrete I type girder bridges utilising nonlinear finite element (FE) analysis. RF has been conventionally calculated either by ultimate strength design (USD) or allowable stress design methods in terms of live load effects. This study introduces nonlinear FE analysis as a new approach to estimate the RF. In general, nonlinear FE analysis is considered as one of the most efficient methods to simulate structural behaviour. This method can also simulate a live load effect, which is very important for the load carrying capacity of structures. To apply nonlinear FE analysis, an FE live load constant was conceptually suggested to estimate the RF. On comparing the RF obtained via the conventional method of USD, it was found that the RF estimated by nonlinear FE analysis approach has almost the same value. Hence, the nonlinear finite element method-based RF methodology can be efficiently used to estimate the load carrying capacity of bridges.