Structural defects for condition assessment of existing bridges: some results of a territorial case study.

Recent events involving the tragic collapse of existing bridges have led to an increasingly detailed study of infrastructure and its maintenance. Italy's intricate road system has a large number of existing bridges demanding urgent and costly maintenance interventions. This study presents a critical review of several defects inspected on existing bridges located in the Basilicata region. The work is addressed at describing the defects surveyed, and at critical evaluating the main causes also due to the interaction with the environmental context surrounding each bridge analysed. Moreover, the paper discusses on how the detailed context knowledge can help to properly identify the correct maintenance intervention on existing bridges.