Project Details
Verification of subjection to EIA of seismic upgrading of viaducts along the A24 motorway, Tornimparte – L’Aquila Ovest section
Description
The A24 highway connects Roma to Teramo, passing through L’Aquila, and is characterized by alternating tunnel and viaduct sections. The highway route Tornimparte – L’Aquila Ovest is of particular importance as it constitutes the richest part in constructions in the branch connecting L’Aquila with the A25 freeway and the Rome-bound branch of the A24 (Tarano directional junction). After the seismic events that hit center Italy in 2009, seismic upgrading of the viaducts along the highway track became necessary. This is also in light of the vital role that the infrastructure had during the earthquake and the legislative changes introduced by the Law 228/2012 art.1 comma 183, which highlight the strategic nature of the A24 and A25 highways for civil protection purposes. The project involves the seismic upgrading of all 17 viaducts in the A24 along the Tarano – L’Aquila Ovest sections.
Five types of general intervention have been identified:
Type 1: Remaking of the viaduct with a new artifact on the ground and new track
Type 2: Remaking of the viaduct with a new artifact on the ground
Type 3: Substitution of the piers and platform
Type 4: Construction of the new platform only
Type 5: Substitution of part of the viaduct span with embankments and the remaining ones with new piers and platforms
The interventions are designed in such a way to guarantee a lifespan of one hundred years through the use of innovative technical solutions and extremely advanced performance materials.
As a result of the preliminary discussions between the Proposer and the Competent Authority for the EIA (Ministry of the Environment), for the three viaducts for which the type 4 (New deck) project is planned, i.e., S. Onofrio, Raia, and Aterno, it was decided to submit an environmental Pre-screening according to art. 6, comma 9 of Dlgs 152/2006 and subsequent amendments and additions given that these interventions are limited to the reconstruction of the highway platform for which the construction sites and working areas will be located exclusively along the highways lanes.
Furthermore, it was decided to submit the Rampa Tornimparte viaduct, the only viaduct for which the Type 1 intervention is planned, to a separate EIA procedure.
Therefore, all the other viaducts were examined in a single Preliminary Environmental Study for the purpose of the EIA admissibility verification according to art. 19 of Dlgs 152/2006 and s.a.a. It should be noted that the EIA admissibility verification procedure was concluded with an opinion of non-subjectivity.
Specifics of the study
Wildlife crossings: As part of the project, particular attention was devoted to the designing of wildlife crossings, especially near the viaducts where the existing structures will be replaced with new earthworks. Without these measures, the new structures could act as physical barriers to animal movement. To address this, the project includes the installation of hydraulic box culverts — one for each viaduct — appropriately sized to accommodate the local wildlife, including medium-sized mammals such as foxes, wolves, badgers, porcupines, and wild boars.