Pratocarasso-Galbisio boardwalk | Bellinzona | 2009
Steel link between the banks of Ticino river
Città di Bellinzona - Dicastero opere pubbliche e ambiente
Ambrosetti Mozzetti Siano Architetti, Bellinzona
Petoud Partner SA, Bellinzona
Officine Ghidoni SA - Ferriere Cattaneo SA
There were many reasons why a boardwalk over Ticino river in Bellinzona, between Galbisio district and Pratocarasso district, needed building. On the one hand there was the newly built Scuola media 2 that brought a remarkable attendance of students from North Bellinzona and the neighbouring municipalities, on the other hand there was the upcoming growth of the new buildable lot ̒Pratocarasso nord̕ ̕ that had a huge residential area.
The new boardwalk fits into the landscape context as a firm and clear connection element between the two Ticino river’s unsinkable banks, crossing many flood plain areas and their vegetation, and raising in an essential way with respect to the formal complexity of nature.
Total length: 159.700 m
Width (flat arch): 3.000 m
Total weight 232 tons
The boardwalk structure highlights a direction of the boardwalk itself that is determined by one distinctive topographic context. A considerable exposure to the usually present North wind characterizes this context, too. So, an asymmetrical structure – one side is both a supporting and protection element, the other side is open towards the valley and looks to the town – of the new building is reasonable.
The deck is completely made of steel and consists of the following elements:
- A single box main beam
- Cross beams jutting from the main beam
- Flat arch built as an orthotropic plate
- Full concrete piers and abutments
- The lighting, made of LED lights installed under the walking surface, complements the coloured surface and highlights the path
- A transparent glass insert is combined with the lights to allow a downwards view from the main beam lower side relating to the underlying landscape, from the flood plain vegetation, to the river pebbles and water movement.
The whole boardwalk had been assembled in the workshop and moved to the building site divided into 9 stumps. It had been moved on special trucks where the stump had been placed horizontally so that, in the building site, it had to be rotate 90° in order to place it to its final geometry.