GE 05.21 – Port Hub Road Network La Spezia – SS No. 1 “Via Aurelia”. Access road network to the Port Hub of La Spezia – Variant to SS 1 “Via Aurelia” – 3rd lot between Felettino and the motorway link – 2nd functional section B from the BuonViaggio interchange (excluded) to the San Venerio interchange (included), including environmental monitoring during construction and post-construction.

Project objective

The intervention aims to complete Section B of the access road network to the Port Hub of La Spezia – 3rd lot. This independently functional segment runs from the Buonviaggio interchange (Section A) through the Felettino I natural tunnel (777 m) and the San Venerio I viaduct (100 m), up to and including the San Venerio interchange. Overall development 1,035 m, cross-section C1 – secondary extra-urban road.
The assignment covers the buildable construction design starting from the Executive Design (PE) and the accepted improvements, including consistency checks among structures/architectural works/systems, engineering of the solutions and optimisation of construction activities; an additional geotechnical study (surveys/instrumentation where required, characterisation and design of the works) and the executive road and structural design of the engineering structures. Continuous design support to the site is included (targeted variants where necessary), as well as BIM as-built at completion.

Main works within scope

Felettino I natural tunnel: following the stabilisation and safety works on the landslide slope below the Carozzo settlement, completion of the tunnel, whose excavation was halted on 25/01/2013 due to instability at chainage 2+460; 36 m were excavated from the south portal (2+497→2+461) and 181 m from the north portal (1+805→1+986). Given the limited cover and the critical context, an artificial tunnel is planned with perimeter diaphragm walls, subhorizontal drains L=40 m, permanent top slab, underground excavation with two levels of temporary struts, base slab, secondary lining/final cladding and intermediate slab with final backfilling. A service tunnel is also planned for access to the tunnel.

Drainage works and stabilisation of the Carozzo slope: prior to constructing the artificial tunnel, all safeguard works on the slope below the Carozzo settlement, located uphill of the tunnel, shall be implemented: 12 m deep drainage wells with radial arrays of subhorizontal drains, adequate discharge pipelines, and consolidation of the head scarp of the landslide area by means of a row of subhorizontal drains L=25 m.

San Venerio I viaduct: construction of the deck with integrated acoustic/safety barriers; elastomeric bearings on piers and abutments already built; reinforced-rubber expansion joints.
Minor works: completion/construction of walls at the San Venerio interchange and at the south portal of the Felettino I tunnel; completion of channel works and construction of the road formation, signage and drainage/water management.