Preliminary assessment of pre-1980 girder bridges in the framework of the Italian Guidelines

Abstract

The Italian Guidelines issued by the Ministry of Infrastructure and Transportation are devoted to preventing damage on road bridges caused by the lack of maintenance and, in turn, avoiding safety or service problems affecting the infrastructure network. The multilevel approach foreseen by the Guidelines develops through the first three levels to attribute the Class of Attention, whose result indicates subsequent steps for more detailed assessment and monitoring actions to be undertaken. One of these actions is the preliminary verification which is performed by comparing stress values generated by the design load schemes used at the time of construction with the ones obtained by applying the current code. In this paper, preliminary verifications are performed on a series of simply supported girder deck models representative of the Italian state road bridges, obtained through a statistical study on a bridge inventory. Therefore, some performance indices related to the main bridge components are obtained with respect to shear and moment stresses for different bridge configurations in terms of the number of beams, span length, and carriageway width, which can be useful for rapid preliminary assessments of similar bridges.