Innovative devices for the base isolation of existing buildings

It is well known that pre-existing buildings are often inadequate to resist strong ground motions, and that their seismic rehabilitation is not an easy task. Several studies available in the to-date literature have shown that seismic isolation is a cost-effective and efficient method that can be employed to protect existing structures from earthquakes. A new class of performance-based seismic isolators has been proposed in recent studies, making use of pentamode lattices confined between stiffening plates. The present work illustrates experimental results concerned with shear and compression tests on physical (reduced-scale) models of pentamode bearings, and discusses the use of such systems for the base isolation of existing buildings. Given results highlight the special ability of such systems to behave as tension-capable and performance-based systems, whose mechanical properties are driven largely by the geometry of the lattice microstructure (i.e, such systems behave as mechanical metamaterials), and can be finely adjusted to the properties of the structure to be protected.