A patent to protect machinery and artworks from earthquakes and vibrations

Protecting the artworks during an earthquake, safeguarding an electrical transformer or a machine by preventing the vibrations produced during normal operation from propagating through the building. Two needs, seismic and anti-vibration, which until now required different solutions, and now brought together in a single device: an isolator for non-structural elements. This is the innovation at the heart of the patent developed by Politecnico di Milano, within the research group led by Professor Claudio Bernuzzi and researcher Marco Simoncelli of the Department of Architecture, Built Environment and Construction Engineering-DABC, through Executive PhD candidate Ahmed Awad in synergy with the company Soleco Engineering.

The new isolation system is designed to protect the non-structural elements of buildings: all the equipment that is not part of the load-bearing structure but is essential for the operation of hospitals, industries, infrastructures and museums. “Let us imagine a large air-conditioning system, an uninterruptible power supply (UPS) unit or even a museum display case containing precious works” explain Claudio Bernuzzi and Marco Simoncelli “Firstly, they must be protected from the effects of earthquakes and external vibrations, such as those generated by trains or underground railways; while at the same time, if they are machines, the vibrations produced during normal operation must not propagate through the building that houses them, disturbing those who work or live there”.

At present, for many categories of non-structural elements and machinery there are no truly dedicated seismic isolators on the market, and those that do exist often do not integrate vertical restraint systems, nor do they allow adequate vibration isolation. This is the innovative aspect of the patent: to ensure effective seismic isolation, while maintaining high levels of vibration isolation performance.

Its operation is simple: the machine or element to be protected is placed on specially designed elastic supports, specifically developed to allow the object to oscillate slightly and rotate in the direction in which the risk of damage would otherwise be greater. This controlled movement modifies the dynamic response of the system to seismic actions, reducing its vulnerability. To prevent excessive oscillations and limit the risk of instability or overturning, the system also incorporates a viscoelastic damper capable of dissipating excess energy.

The advantages are various: the system is designed and calibrated to measure for each individual application, by analysing the dynamic behaviour of the object to be protected in order to define the characteristics of the supports correctly.

“An important aspect of the invention concerns the frequency-dependent damping behaviour: the system is designed to offer a high level of dissipation at the low frequencies typical of seismic action and, conversely, more limited damping at the frequencies associated with the machine-induced forces, so as to preserve maximum vibration isolation efficiency during normal operation,” explains Ahmed Awad, R&D Manager at Soleco Engineering and Executive PhD candidate at Politecnico di Milano.

The device that has been conceived also makes it possible to simplify installation, offering a single integrated solution where previously two were needed, with consequent savings in space, costs and complexity.

“The collaboration with Politecnico di Milano enables us to combine Soleco Engineering’s industrial experience with the state of the art in scientific and technological research,” underlines Valeria Vezzo, CEO of Soleco Engineering. “For us, investing in innovation means transforming research into concrete, high-performance and reliable solutions, capable of offering our clients cutting-edge technologies and anticipating the new needs of the market”.