Retrofitting assessment and numerical models for the historical timber roof structures of the towers of Valentino castle in Turin

The paper analyses a reinforcement intervention conceived by one of the authors (C. Bertolini) and performed on the historical timber roof structure of the Valentino Castle in Torino (Italy) some thirty years ago. The timber roof of the towers, dating back to 17th century, is a three-dimensional frame structure with a height of about 12 m. In the transversal direction four main great trusses are present, and two small trusses are placed close to the transversal masonry walls. The pitch is strongly inclined. A ridge connects the structure in the longitudinal direction of the timber roof, in addition to five series of purlins and three orders of overlaid frames with stiffening functions. This structural complex is firmly secured to the covering planks that support the tiles of black stone. The intervention was carried out with timber elements anchored to the ancient masonry walls, in order to improve their seismic behaviour. This intervention proved to be particularly innovative, since at that time the regional area where the castle is located was not yet considered a seismic area by the national standards. Laser scanning surveying, non-destructive investigations and numerical simulations are adopted in the present study, in order to assess the efficiency of the intervention and the present condition of the joints.