Optimal design of single-degree-of-freedom vibro-impact system under harmonic base excitation

Strong seismic excitations can induce considerable displacements in base-isolated structures. These may in turn cause damage to the isolation system or impacts against adjacent structures in the event of an insufficient seismic gap. A strategy of reducing displacements can be achieved through the interposition, between the isolated structure and adjacent structures, of deformable and dissipative devices, called bumpers. In this paper, the response of single-degree-of-freedom (SDOF) base-isolated systems subjected to sine excitations and whose displacements are limited by optimally designed bumpers are analyzed, the bumpers being designed according to an optimal design criterion.