PSI - Issue 84

M.P. Petrangeli et al. / Procedia Structural Integrity 84 (2026) 135–142

139

After the completion of the temporary bridge all the utilities have been moved on it from the adjacent “Ponte dell’Industria” so that the works for its retrofit could be started. 5. A new deck for supporting the weight of the old one The new structural deck of the bridge, introduced for retrofitting the old one damaged by fire, is a 107 meters three span continuous beam with two main extradosed steel truss beams 2.7 m deep and a steel orthotropic deck; the new deck is designed to carry the traffic loads, without any limitation, in addition to the weight of the old parabolic truss beams, too deteriorated and weakened to carry any kind of load. The cross-member location, as well as the geometry of the new truss beams, has been defined in a way of being shadowed by the old parabolic truss beams, thereby disguising their loss of structural function. The following pictures show a comparison between the cross section of the bridge before and after the present renewal.

Fig. 8 (b). The new enlarged cross section of the bridge with a 7.50 m roadway, 0.64 m service/emergency sidewalks plus 2 m pedestrian/bicycle pathway on each side

Fig. 8 (a). The original cross section with a 5.10 m roadway and 1.2 m

Fig. 9. New longitudinal view after the completion of works

As specifically requested by the “Soprintendenza Speciale di Roma - Archeologia Belle Arti e Paesaggio”, the office of the Italian Ministry of Culture dedicated to the preservation of arts and monuments, special attention has been paid to designing of all members and joints of the new structural truss beam in a way of replicating the post industrial style of the original bridge but without renouncing the use of state-of-the-art in fastening technology; as a result all the bolted joints have been assembled using slip resistant HRC bolts that provide maximum efficiency in terms of execution time and torque control, while at the same time, having the characteristic HRC rounded head, replicating the old style of the outdated riveted connection of the original bridge (CEN, 2018).