GNGTS 2022 - Atti del 40° Convegno Nazionale

GNGTS 2022 Sessione 2.2 367 STRUCTURAL MONITORING OF A HIGHWAY BRIDGE IN A HIGH-SEISMIC HAZARD URBAN AREA A. D’Alessandro 1 , S. Bongiovanni 2 , A. Costanzo 1 , A. Di Benedetto 3 , A. Figlioli 2 , S. Scudero 1 , S. Speciale 1 , G. Vitale 1 1 Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, Rome, Italy 2 Università di Palermo, Dipartimento di Scienze della Terra e del Mare, Palermo, Italy 3 Università di Palermo, Dipartimento di Matematica e Informatica Palermo, Italy Introduction. The stress factors acting on the structures can be due to natural or anthropogenic factors: earthquakes atmospheric agents (wind, thermal cycles), vibration due traffic flow, applied loads. All these factors, may lower the resistance properties of the structure therefore the Structural Health Monitoring (SHM) represents a fundamental tool to integrate and support conservation strategies of infrastructures and to preserve their functions. The function which describes the behavior of a structure will be dependent on the structural parameters obtained with the building monitoring. Such parameters may change after an earthquake, or even after extreme phenomena, and the continuous SHM enable to verify if the general parameters of the building have changed as today widely accepted (Calvi et al. , 2006 for a complete review). In the framework of RAFAEL (System for Risk Analysis and Forecast for Critical Infrastructures in the AppenninEs dorsaL Regions) project, the case study as critical infrastructure to monitor is a bridge in Catania (Sicily, Italy). This viaduct is called “San Paolo bridge (Fig. 1); the choice of this structure has several reasons: i) it is the longest viaduct in the highway surrounding the city of Catania and part of the E45 European motorway corridor; ii) the seismic hazard of Catania is among the highest in Italy (expected horizontal peak acceleration up to 0.25 g); iii) the viaduct was built about 35 years ago, when the seismic classification and building codes were different. In this paper, we present the preliminary results of the tests performed for the characterization of the structure and its foundation soil. Fig. 1 - a: Google Earth view of S. Paolo bridge (the arrows indicated the segment under investigation) and plan view of sensors location for the experiments; b: lateral view (southern flank) of the structure; c: location of the posthole (50 m deep) seismometer and ground-level accelerometer.