Reliability-based safety assessment of bridges

A reliability-based safety assessment method is proposed for bridges in the Korean expressway. In addition to the current Korean guideline for the safety assessment, some available international safety assessment codes and guidelines for bridges are reviewed and compared. To examine the proposed method, field tests were carried out on a PSC girder bridge in a Korean expressway. Static and dynamic truck tests were carried out to update the analytical model for the bridge. The assessment results by different method are compared. The comparison demonstrated that the assessment using the current Korean guideline is very conservative compared with the others. The evaluation using the proposed assessment method, considering the reduced uncertainty in the assessment and corresponds to the newly issued bridge design code in the limit-state format, revealed a considerably improved rating factor. To take the characteristics of the limited truck traffic of the expressway into account, a live load model is constructed using the site-specific truck information in a statistical manner and used to evaluate the load rating. The reduced live load of the expressway increased the rating factor of the tested girder bridges in a Korean expressway.