In May 2012 a series of strong earthquakes hit northern Italy in an area between the provinces of Modena, Mantua and Ferrara.

Earthquakes hit northern Italy

The magnitude of the shock was defined by the INGV (Institute of National Geophysics and Volcanology) as being compatible with the revision of seismic hazard in 2004. It is believed that the thrust of Mirandola may be the potential source of earthquakes with a magnitude of about 6.0.

Despite scientists predicting and mapping the possibility of earthquakes of this magnitude, the pledge of lives and damage to homes and businesses has been very high.

Images of warehouses appearing seriously damaged, when not completely destroyed, generated a stir in the media with this particularly striking footage of the collapse of a warehouse storing maturing Parmesan Cheese.(http://www.6aprile.it/media/video/2012/06/10/video-il-crollo-delle-forme-di-parmigiano-durante-il-terremoto-in-emilia.html)

Parmesan cheese is at the heart of Italy’s culinary excellence, produced in around 3 million forms every year. Manufactured in a designated area with a Protected Designation of Origin (PDO), the Parmesan is still produced following the traditional method of manufacture and ripening.

Within the maturing cells alone, the Emilia earthquake last May generated more than €150 million of damage!

How Can That Be?

Parmesan cheese is at the heart of Italy’s culinary excellence

In order to assume an answer you should take a step back to when the regulations considered racking in the same way as furniture and did not consider the risk related to the large masses stored at high altitude in the event of earthquakes, especially in areas where personnel works continuously. Paradoxically, automated warehouses without a great number of personnel were asked to be designed to somehow consider parameters relating to the earthquake, where there isn’t presence of staff, were asked to be designed considering somehow parameters related to the earthquake.

In 2008, following the tragic earthquake in L’Aquila, new NTC (technical standards for construction) were issued to remedy shortcomings of previous legislation. The new seismic map was incorporated as defined by the INGV as a result of extensive studies on the territory morphology.

Unfortunately, also in this case the racking (Self-supporting) is not normed clearly as it differentiates to traditional buildings in the following points:

• Unlike a normal metal structure, racking components are industrial products across series.
• The mass of the racking is normally much lower than the total mass of the stored goods.
• The stored goods is variable, depending on the load condition of the warehouse.
• The stored goods are not bound to the shelves and, in case of an earthquake the friction of the pallets on the racking and between individual packages within the same pallet help dissipate generated energy.

To meet this lack of legislation, the NTC itself mention the possibility to draw on technical standards of proven validity as such FEM norms.

Returning then to the question of how could this happen, the answer is that warehouses damaged by the earthquake were built without considering seismic forces or by referring to regulations and / or seismic maps now obsolete (but valid at the time of construction).

Whilst considering a cyclical seismic event can be a lengthy process (in Emilia to detect an earthquake of similar magnitude must go back to 1639 – source INGV) why not also cover the upgrading of existing buildings upon taking into force of new norms, rather than enforce it only for new buildings?