The project for this cantilevered dog-legged stair, about 6 metres high, was an interesting challenge: the structure (shaped like a half-helix) is in fact interrupted by three intermediate landings.
The structural calculation was accomplished mainly basing on the resistance for the shape of the stair, and it was validated through a computer calculation, carefully looking after the realisation and the good arrangement of the reinforcing irons on the construction site.
Once the realisation of the concrete slab (only 20 cm thick) was completed, we carried out an additional loading test in order to confirm the results of the structural calculation already done. We did that by using some loads to measure the deformations of the structure and to confirm the resistance. The monthly magazine L’industria Italiana del Cemento (ICC) dedicated a three-page article to this project.