Silvestri Plant

Dormelletto (NO) – 1956

Architecture: Aldo Favini
Structures: Aldo Favini
Client: Ernesto Silvestri

Structural scheme
Roof of thin vaults in prestressed reinforced concrete, simply resting on the supports.

«…Machine shop … of about 750 m2 … with a rectangular form measuring 20.10 m in width and 37.50 m in length … roof composed of five thin shed vaults in circular-prestressed reinforced concrete, with span of 20.10 m and base intervals of 7.50 m. The thickness of vaults, 10 cm, increases to 15 cm and 20 cm respectively in the connections with the tympana at the extremities and the border beams; the lower ones have a height of 135 cm and a thickness of 25 cm, while the upper have a height of 30 cm and a thickness of 25 cm. The vaults rest on full tympana with a thickness of 8 cm, supported by pillars placed only on the perimeter of the building, at intervals of 7.50 m.»

FM degree thesis 2003.

«…a new plant of about 750 m2 for the Officine Elettromeccaniche Ernesto Silvestri has been built at Dormelletto di Arona (Novara province). In the design phase the following main factors had to be taken into account:
a) the need to abolish internal intermediate structures to support the roof, in such a way as to permit the greatest freedom in the positioning of the machinery, to facilitate production cycles;
b) the need to achieve abundant natural lighting, given the characteristics of the production in a precision machine shop…
…The temporary shoring of the structure was done in wood, by means of centering arranged at intervals of 75 cm supported by horizontal lintels and vertical posts. The concrete utilized was 3.75 ql of 680 per m3 cement, 0.4 of sand and m3 0.800 of gravel. The prestressing cables were housed in sheaths of metal sheeting. The operations of tensioning and blockage of the cables involved the use of the Favini system (licensee S.T.I.A.P. of Milan, Via Crivelli 12) with anchoring of 6 lines with a diameter of 5 mm. After the tensioning of the cables, the sheaths were injected with cement and a special additive. The ends of the protruding cables of the anchors were bent and embedded in the pour of the eaves platform.»

By AF 1960.

Publications
• AF, Volte sottili a shed in cemento armato precompresso, in “Giornale del Genio Civile”, n. 2-3, 1960.