Structural evaluation and strengthening of a reinforced concrete bridge

ABSTRACT. This paper deals with the structural evaluation and strengthening of a reinforced concrete bridge over the Arno River in Italy. In 1996 truckload tests and finite-element calculations were performed to assess the bridge condition. The structure was found to be inadequate to bear both the first- and the second-class road loads prescribed by the Italian Bridge Recommendations. The choice of its demolition and reconstruction was rejected, however, since it was too expensive and required a lot of time as well as dramatic conveniences for the traffic and the road network. So a strengthening design was developed to upgrade the structure to a first-class bridge. The restoration work was performed from September 1999 to September 2000 and dealt with the main structural elements. After the completion of the work, the flexural stiffness was about 20% greater than that in the old structure, and the flexural strength at the midspan of the interior span was 70% greater.