PSI - Issue 84

Giovanni Stasi et al. / Procedia Structural Integrity 84 (2026) 789–796

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thickness varying from 40cm at the base to approximately 22cm at the top. The ribbed walls are connected, at a vertical spacing of 6.0m, by 15cm thick horizontal slabs stiffened with 90cm high ribs. In the early 1970s (1972-1973), the deck was reinforced with an average thickness of 17 cm. After the reinforcement, the thickness of the deck is 37 cm. a b

Fig. 3. (a) girders section; (b) pier section.

3. Mechanical characteristics of existing materials The average cylindrical strength of the concrete, evaluated on 16 cores extracted from the substructures, was approximately f cm =30 MPa. For the reinforcement, reference was made to 12 extracted specimens, whose average yield strength was approximately f ym = 380.9 MPa. For the other mechanical and geometric characteristics of the structural elements, reference was made to the design values and information obtained from the construction accounting drawings. The base sections of the piers are reinforced with vertical reinforcement of larger diameter (varying from  18 to  22 depending on the height of the pier) at the corners of the ribs and with 10+10  12 bars on both sides of the walls. These reinforcements are tied with three 10  20 stirrups and ten  6 pins. 4. Foundations and geotechnical and geophysical characteristics of the soil The subsoil of the site is characterized by a surface layer approximately 5-6 m thick of gravel mixed with clayey silt (300 m/s

Fig. 4. X-direction SLC response spectra: (a) 7 scaled natural signals, (b) average spectrum

The search was conducted using signals extracted from Rexel Web (ITACA database) and the European Strong Motion database. For this study, spectro compatible signals were sought both at the SLC (for device sizing) and at the SLV with return periods associated with a v N = 50 years.