The use of wooden floors has been for millennia the “compliant solution” for the horizontal elements of the buildings of the most
different types, due to their lightness, elasticity, resistance, flexibility of use and ease of realization. Recently, particularly for
buildings located in seismic areas, it has been argued that their deformability was a serious defect and not only in literature, but
also in the Official Rules, it is recommended or required that both the existing wooden floors, and new ones, should be made
infinitely rigid and non-buckle able in their plane, through the application of reinforced concrete slabs, tied through connectors to
the wooden beams. This solution has, however, turned out to be worse than the disease that tried to cure, on one hand causing the
rotting of the wooden parts in contact with the concrete, and on the other determining – under earthquake forces - torque such as
to cause the collapse of parts of the walls, or of entire building units. At La.Te.C. - Laboratory of Building Technology - of the
School of Engineering of the University of Basilicata, it is an ongoing a complex research which investigates for years the use
and improvement of forest resources of Basilicata and the possibility to use for various purposes in construction the essence of
hardwood Quercus Cerris L. (Turkey Oak). The research performed till now has shown the great interest on the use of thermohygrometric
“modified” Quercus Cerris to tackle the problems set by the refurbishment and/or the restoration of buildings in the
historical centres; it has been developed a construction system for wooden floors, based on the use, in addition to the traditional
floor joists in vertical planes, of trusses of considerable height and therefore very rigid, arranged beside the external walls or
internal ones in horizontal plane, with hinge tie at the ends to wooden chains bound to the perpendicular walls. These reticular
trusses are able to retain rigidly in their position the external walls subject to seismic action, preventing from their tilting out of
their plane, and then forcing them to express all the shear strength or buckling resistance of which they are capable. To facilitate
the use of this system by the designers, it has been arranged and implemented a calculating sheet, upgraded to the most recent
Italian Regulations
