Construction of the Via alla Costa bridge and related access road network in the Municipality of Vado Ligure (SV).

Project objective

The objective of the study was to define the new Via alla Costa bridge over the Segno stream and the related access road network (plan and profile study of the alignments and tie-ins with Via alla Costa and Via Piave): demolition of the existing bridge and its reconstruction as a single-span structure, in order to eliminate the in-channel pier, is required for hydraulic-risk mitigation, in accordance with previous detailed hydraulic studies.

Main works

Alignment
The axis of the new bridge was aligned with Via Sabazia, opposite Via alla Costa on the other side of Via Piave.
Along the new Via alla Costa axis, starting from the municipal warehouse, the alignment deviates from the existing one and, through a curved embankment, the road elevations are tied into the new bridge; once the bridge is crossed, the road ties into Via Piave with a T‑junction.
On Via Piave, in the section between the existing bridge and the railway spur, the road profile is redefined by means of a vertical raise which, at the bridge tie‑in (maximum section), reaches 1.70 m (average 1 m), in order to meet the new road levels required by the minimum hydraulic freeboard; this made it necessary to redesign the accesses both to the nearest condominium and to the service station.
With the new road configuration, the pedestrian and cycle–pedestrian routes were also redesigned.

New bridge
The deck of the new bridge, first-category, with a curved profile and a length of 42.60 m, consists of a steel load-bearing structure with upper tubular arch profiles of variable section, with an axis inclined 10° outward, connected to the trapezoidal closed box side girders through stay cables.
The cross-beams consist of HEB 1000 sections topped by a 25 cm thick cast-in-place reinforced-concrete deck slab.