VDP Srl

PROJECT DESCRIPTION

The Circumvesuviana Railway upgrade involves the doubling of the railway line and the construction of the new station “Stabia Scavi” is a significant part of this project. In fact, the new station will replace Via Nocera Station constituting also a functional integration of the service and it will be an important road/rail interchange hub in the heart of the urban fabric of Castellammare di Stabia.

In particular, the new station will have three levels, designed to allow a rapid access from the pedestrian gallery to the ticket offices on the ground floor and to the train boarding area located 4 m above. The train platform level will be partially in correspondence with the station building and partially inside a soundproof tunnel designed to minimize the acoustic impact on the surrounding area. The tunnel project consists of a transparent covering vault made with polymethylmethacrylate (PMMA) sheets presenting a thickness of 12 mm.

Furthermore, a multi-level underground parking lot and the related connection with the station will be built next to the infrastructure.

PROJECT CHARACTERISTICS

The work carried out by VDP involved the study of the passive acoustic requirements of the tunnel in order to evaluate the noise emission levels on sensitive receptors, such as the two hospitals on the sea side and the school complex on the mountain side.
Moreover, VDP carried out a noise analysis regarding a potential opening in the central upper area of the vault in the tunnel section close to the station. This opening would be functional to the diffusion of heat and exhaust fumes. In this evaluation, external noise sources, such as road infrastructures, were not taken into consideration.

The calculation of the noise radiated inside the tunnel, and partly transmitted outside, was performed using a detailed three-dimensional software able to define sound propagation taking into account numerous parameters and factors as the different types of materials, structures and building layouts considered for the tunnel construction.

The following layouts were studied:

• Absence of the soundproof tunnel (i.e. construction of only the basic station building in reinforced concrete);
• Completely closed PMMA soundproof tunnel (no opening);
• PMMA soundproof tunnel with upper opening and transverse vertical elements with respect to the railway axis;
• PMMA soundproof tunnel with upper opening and longitudinal vertical elements with respect to the railway axis.

For what regards the multi-level parking lot, VDP prepared an Environmental Monitoring Plan focusing on the most significant aspects linked to the environmental conditions of the area, ensuring the integration of the overall relevance of the surveys and their economic sustainability.
After the evaluation of the environmental elements characterizing the territory and the results of the previous analysis, the Environmental Monitoring was extended to the following environmental components, providing a total of 10 survey locations:

• Atmosphere;
• Noise;
• Vibration;
• Underground Waters.