The ancient timber roofing structures in Emilia Romagna region
Marzo A., Marghella G., Indirli M.
Articolo Rivista internazionale con referaggio
Widespread survey aiming at the evaluation of both vulnerability of the structures and safety of the buildings have been carried out, after the seismic events occurred on may 20th and 29th 2012 in Emilia-Romagna districts, with reference to different typologies of structures (bridges, industrial factories, residential houses, etc.) made by various kinds of materials (masonry, reinforced concrete, precast/prestressed reinforced concrete, mixed). During the surveys, several typologies of ancient timber covers have been verified, which often evidenced lack in terms of earthquake-proof features. In contrast, some of them dating approximately on 18th or 19th century, show original technology for the construction according to the seismic mitigation measures, although the Emilia-Romagna region has been classified as a seismic area in 2003, only. Clearly, the attention to the behaviour of the covering structures against the horizontal actions was due to the historic memory related to earthquakes occurred many years before or simply due to a good construction practice lost during the following years. At first, the paper deals with an overview about the timber roofing typologies existing in the old centre of the Padana Plain cities. Then, it is devoted to explain the analysis campaign carried out on an ancient timber covering structure selected as a study case. In particular, the chosen roofing structure is dated about two century ago and represents an example of good construction to be followed for both retrofitting existing structures and realizing new ones. It covers a valuable building located at the old centre of Cento (Ferrara), which is one of the city stricken by the May 2012 earthquakes, in particular subjected to damage during the 29th event. The analysis campaign has been carried out in three subsequent steps: 1) in-depth visual and geometrical survey; 2) in-situ non destructive tests for the material characterization (timber elements and iron connections); 3) sophisticated FEM model, set up according to the previous phases results. The aim of the analyses is the seismic behaviour characterization, in order to point out any upgrading requirements and, finally, the restoration intervention proposal for the timber structure preservation, by using both reversible and sustainable techniques.
Marzo A., Marghella G., Indirli M. "The ancient timber roofing structures in Emilia Romagna region" Advanced material research 778