Italy is a territory with high seismic hazard. Throughout history, and also recently, numerous earthquakes have taken place, which have devastated entire cities, causing thousands of victims. Until a few decades ago, there were no technical and scientific tools to deal with this risk, which was suffered by unarmed populations.
Today, fortunately, the situation is different, since evolution in the field of engineering has made it possible to frame this physical phenomenon and to provide theoretical tools to design buildings that are able to guarantee the necessary safety to safeguard human life. Recently, the entry into force of the “New technical standards for construction” has deeply innovated the field of anti-seismic structural design, both in structural calculation methods and from that and in seismic classification of the national territory.
The recent earthquakes that have hit Italy are tragically significant to demonstrate the problems of buildings built in the traditional way, or designed with design criteria that comply with the old generation technical standards. It should therefore be noted that even recent buildings, which have retained their eartquake resistance, were declared condemned after the seismic event, due to the collapse of the infill works.
It is known that, for this problem alone, there have been dozens of victims. Not to mention the ordinary brick buildings, affected by more or less extensive collapses… The new technical standards, with respect to which the load-bearing structures made with the ICF ITALIA system show full compliance and ease of verification, were born with the goal of avoiding the problems described above.
To achieve this goal, the regulator has introduced important restrictions from the design point of view which, in the case of traditional structures, affect construction costs, due to the increase in seismic actions to be applied, construction details to be respected, minimum dimensions for beams and pillars or for brick walls. With ICF ITALIA system it is possible to design anti-seismic structures that fully comply with the new technical standards without any additional cost.
The structures built with ICF ITALIA system, thanks to the favorable distribution of the stresses on the large resistant elements (extended walls) and therefore to the low stress states, can even be designed in a “linear elastic range”. This means that even after a violent seismic event, a building built with ICF ITALIA system – if well designed – can be immediately accessible! Furthermore, the reinforced concrete walls that make it up, solidly connected to each other and to the floors, are not subject to overturning or expulsion phenomena.
The advantages deriving from such performace (which, again, are intrinsic in the structure and do not require additional costs) are also appreciable from a “social” point of view, since the post-earthquake phase of the precautionary evacuation (immediate occupancy) and that of temporary housing are eliminated.
È un luogo comune della progettazione sismica quello di ritenere che prestazioni che consentano alle costruzioni di rimanere in campo elastico (completa agibilità), anche a seguito di eventi sismici “violenti”, comporti costi insostenibili per la società; le strutture a pannelli portanti continui appaiono in grado di smentire questo luogo comune fornendo a prezzi competitivi strutture altamente sismoresistenti (prof. Tomaso Trombetti, Università di Bologna).