Floor response spectra for moderately heavy nonstructural elements attached to ductile frame structures

Abstract

This paper presents a methodology for predicting the seismic peak response of vibratory single-degree-of-freedom (SDOF) nonstructural elements with simple measures. The non-structural elements may be attached to both elastic and ductile load-bearing frame structures. The methodology is based on modified modal superposition of floor response spectra for SDOF oscillators on SDOF supporting structures. Dynamic interaction between the substructures is considered, and thus, the peak response of moderately heavy nonstructural elements can be assessed. The presented results are based on numerical simulations involving 44 ground motion records of the ATC63 far-field set and subsequent statistical evaluation. For several example problems “exact” results are contrasted with outcomes of the proposed methodology. This comparison provides evidence that the proposed methodology delivers sufficient accurate predictions of the seismic peak response of simple vibration-prone nonstructural elements on ductile load-bearing structures.