“Guidelines for the classification and management of risk, for the evaluation of safety and for the monitoring of existing bridges”. Critical analysis and identification of innovative methods to improve the classification of landslide risk.

Abstract

The structural collapses occurred in recent years in Italy have highlighted the need for maintenance on road bridges. To ensure a uniform risk management system, guidelines and related operating instructions have been issued for classification, safety assessment and monitoring of existing bridges. The central focus of the approach is the determination, for each bridge, of the so-called "Overall attention class" that derives from the combination of four partial attention classes that covers: structural and foundational risk, seismic risk, landslide risk and hydraulic risk. This work concerns the identification and subsequent classification of landslide risk for existing bridges. An analysis of the calculation parameters of the attention class relating to hydrogeological risk is illustrated, in order to optimize the evaluations by limiting the subjectivity in the processing. The work therefore presents some methods to determine the propensity for failure of the investigated area in order to avoid incorrect execution of the risk analysis and a proposal to improve the guidelines indicating some innovative methods to estimate the parameters necessary for determining the level of hazard associated with the landslide attention class.