Projects: Roads & Motorways
Restoration of viaduct 'dei Parchi'
Main features of the work:
- 2 separated roadways
- 3 km length for every roadway
- 245 independent spans
- 3 road junctions with high traffic density
Widening for the construction of the 3rd lane
The viaduct 'dei Parchi', located on the Milan Eastern By-Pass Road, develops on two distinct decks constructed in the early Seventies, with a roadway consisting of three driving lanes without emergency lane.
The work, with a length of approx. 3 km per carriageway and a total of 245 spans independent from each other, concerns three busy junctions of the by-pass road (Lambrate, Rubattino, Forlanini) with the relevant inbound acceleration and outbound deceleration lanes. The design was about the widening of the carriageways through construction of two new viaducts in addition to the existing ones, properly linked to the same in order to obtain three lanes in total, plus the emergency lane, and to simultaneously improve traffic on the junctions.
In the stretch in question, the original motorway route develops on two separate carriageways, with a distance of approx. 30 m from each other, featuring desks of 13 m width, made of plates with an overall length of 24 m. The decks are fitted into an offset pier at a distance of 7 m from one end and 17 m from the other, and they lean against each other by means of saddle supports, so as to obtain a sequence of deformed frames. The solution chosen for the widening consisted of two different works, included among the existing ones, repeating the same deformed-frame structure as the old solution with similar geometrical features.
The decks have been designed in such a way that their construction affects traffic as little as possible, as well as to allow progress by successive spans as required by the special structural scheme of the work. Therefore, a special self-pushing structure has been designed in order to allow a sequence with cycles comparable to industrial productions.