A case study for the reliability evaluation of an existing prestressed bridge according to current Standard

The structural reliability of existing post‐tensioned concrete bridges is a non‐trivial topic because of uncertainties affecting many parameters involved in their assessment process. This last is performed according to the current Codes specification through the partial factor method. Such method can be applied considering realistic material properties variability and accounting also for ageing, deterioration, and damage by means of all prior data that can be collected, as stated in present Standards like Fib 80. These data span from existing design specifications up to original design documents and experimental campaigns for the material investigations through in‐situ tests. Regarding existing post‐tensioned concrete bridges, the prestressing cables characteristics are the most important components in the reliability of the final safety verification, but their values (in terms of probability distribution) are affected by many uncertainty sources. This paper focuses on the evaluation of the structural reliability of a real case study by applying the partial factor method and by comparing the results achieved considering the ideal case of perfect knowledge with those achieved considering different levels of knowledge acquired through simulated experimental tests.