HALF A CENTURY OF LIFETIME OF LARGE ADRIATIC BRIDGES EXPERIENCE AND GUIDELINES FOR FUTURE

Seven large reinforced concrete arch bridges were constructed over the past four decades with spans ranging from 140 m to almost 400 m: Sibenik, Pag, Krk (two arches), Maslenica, Skradin and Cetina Bridges. The most famous among them is Krk Bridge, completed 27 years ago but still the largest spanning conventional reinforced concrete arch in the world. Unfortunately, older Adriatic arch bridges, particularly Pag and Krk bridges, suffered greatly over decades of service, due to combination of aggressive exposure conditions and inadequate attention to durability issues which was to the best knowledge at the time. Serious deterioration of structural members with reinforcement corrosion being the major issue, led to many complex and expensive repairs, as discussed in the paper. Croatia is currently placing large efforts to develop a reliable and efficient motorway asset management system to employ lifetime engineering principles when dealing with existing and new structures. In order to do this effectively, bridge maintenance and management strategy needs to be adaptive and learn from success or failures of past actions.