ACB® beams as a light structural solution for the rehabilitation of the Air Vergiate Flying School in Italy

Thanks to their lightness and aesthetic qualities ArcelorMittal's ACB® cellular beams were used for the renovation of the Air Vergiate Flying School at S. Anna in Sesto Calende on Lake Maggiore and gave life back to a “sacred” place of Italian civil aviation.

Detailed information

A building with aviation history

The old building housed the first civilian flying school in Italy established in 1915 adjacent to the seaplane base and the industrial complex for the production of seaplanes. The airplanes of the two world wars were manufactured at this site and from here the seaplanes left for the first heroic transatlantic flights. During the Second World War, the small building also housed the X Fleet MAS. According to a legend that fascinates X-Files and UFO enthusiasts, Mussolini’s Secret Service brought and hid here certain mysterious “unconventional aircrafts” which arrived in the area in 1933.

After being abandoned and neglected for decades, the restoration and development project of the ex-seaplane base was launched. It was decided that the small building be restored to its original use by opening a civil aviation training centre, even if the new pilots will no longer use the calm waters of the lake as a take-off and landing runway, until the water landing area has been reactivated (the Air Vergiate fleet currently uses the Biella Airport as its operating base).

Renovation with ACB® beams: structural lightness guaranteed

The historical building had a pitched roof supported by a metal reticulated Polonceau truss. The approximately 5.8 m height to the underside of the beam allowed the available area to be doubled with the creation of a mezzanine at a height of about 3.50 m. The need to find a structurally light solution for the new storey was obvious in order not to burden with excessive loads the original masonry columns, some of which had deteriorated because of humidity. It was therefore decided to use two intrinsically light materials: steel and wood.

For the metal structure of the new mezzanine, the designers proposed the use of cellular beams with wide circular openings in their webs. Due to their particular aesthetics, these beams remind of the lightweight ribs of the wings of an aircraft and were therefore chosen instead of what would appear a more logical solution, namely the use of a reticular beam in dialogue with the existing one of the roof.

The cellular  beams, characterized by both material and visual lightness, were made from hot rolled steel sections (IPE 400) transformed in the workshop through special processing:  a double continuous sinusoidal cut along the entire web with welding in-line of the two T-shaped elements obtained -, allowed the section height to be increased by 50% (614 mm) and to  create large circular openings in the beams' webs  at 80% of the final height of the beam. Finished with a treatment of aluminium-coloured paint, the light, 13 m long cellular beams reproduce on an enlarged scale the structure of the wings of airplanes.

The parallel beams are arranged obliquely compared to the rectangular plan of the building: during the design, special attention was payed to the visual alignment of the beam openings, which from beam to beam are perfectly in line. Placed at a reciprocal distance of 3.5 m, the beams are hung by rods to the metal truss: besides adding dynamism to the interior space, this particular structural layout allowed the designers to  free themselves  from the problem of the early 1900s walls of the building being out of square.  The floor is finished just with planking of pressed laminated wood of 10 cm, which acts also as brace for the beams-rods pendulum system. In order to hang the system, it was first necessary to reinforce the reticular roof beam with new braces and gussets, inserted in the interstice between the two profiles in C to the truss.

The building of the flying school also has a bar and a multipurpose room available to the community which opens onto the park of the ex-seaplane base, a nature-oriented area that is rich in history.

Project Information

  • Sesto Calende
  • Italy
  • Architect:
    Studio Castiglioni and Nardi/Arch. Maurizio Colombo and Cristian Meletto
  • 2009
  • Client:
    Air Vergiate - Italian Flight Training Organization 001
  • Engineering Firm:
    Ing. Paolo and Marco Lucca
  • Steel:
    ACB® beams: ArcelorMittal
    Technical consultant: Mauro Sommavilla ArcelorMittal Commercial Long Italia
  • Photographer:
    Andrea Raffin forArcelorMittal, Studio Castiglioni and Nardi