Issue 46

F. Bazzucchi et alii, Frattura ed Integrità Strutturale, 46 (2018) 400-421; DOI: 10.3221/IGF-ESIS.46.37 404  reinforcement in the precast beams was not enough to ensure a category II bridge classification;  the presence of a shear fracture along the dapped end corbel promoted the oxidation of the reinforcement bars in the joint;  the passage of II category loads (more than 100 per year) puts frequently the structure close to its ultimate bearing capacity.  the eccentricity produced by a transit misaligned by the carriageway central line significantly increased the loading in the external dapped end joint. These results have been produced by detailed destructive analyses that can not be carried out for an existing structure. This means that the only control parameter that we can adopt in these cases is load checking and protective device installments for delicate parts, as Gerber supports. Figure 5 : Dapped end corbel conditions before the collapse (a) ; humidity presence and water stagnation (b) ; failure loading configuration (c) [1]. Figure 6 : Ancona overpass after the collapse (from web site www.cronacheancona.it) .