Floor response spectra for seismic design of non-structural elements according to the Italian NTC 2018

Seismic performance of Non-Structural (NS) components represents a key aspect in the analysis of both new and existing buildings. A significant number of these components can be classified as acceleration-sensitive and are often assumed dynamically uncoupled from the primary structural system. This assumption supports the widespread use of Floor Response Spectrum (FRS) approaches, which are well-established in the scientific literature and adopted by many building codes. This study provides the background of the formulation reported in the Italian Standards (NTC 2018) for FRS, involved in estimating the seismic demand of non-structural elements. At first, the theoretical basis of the formulation is provided. Then, parametric analyses are carried out on frame structures, aimed at calibrating the formulation proposed for the amplification factor R. Finally, for a case study the FRS derived with the formulation proposed are compared with the ones adopted by several international standards.