Seismic force demands on acceleration-sensitive nonstructural components: a state-of-the-art review

Nonstructural components (NSCs) are parts, elements, and subsystems that are not part of the primary load-bearing system of building structures but are subject to seismic loading. Damage to NSCs may disrupt the functionality of buildings and result in significant economic losses, injuries, and casualties. In past decades, extensive studies have been conducted on the seismic performance and seismic design methods of NSCs. As the input for the seismic design of NSCs, floor response spectra (FRS) have attracted the attention of researchers worldwide. This paper presents a state-of-the-art review of FRS. Different methods for generating FRS are summarized and compared with those in current seismic design codes. A detailed review of the parameters influencing the FRS is presented. These parameters include the characteristics of ground motion excitation, supporting building and NSCs. The floor acceleration response and the FRS obtained from experimental studies and field observations during earthquakes are also discussed. Three RC frames are used in a case study to compare the peak floor acceleration (PFA) and FRS calculated from time history analyses (THA) with that generated using current seismic design codes and different methods in the literature. Major knowledge gaps are identified, including uncertainties associated with developing FRS, FRS generation methods for different types of buildings, the need for comprehensive studies on absolute acceleration, relative velocity, and relative displacement FRS, and the calibration of FRS by field observations during earthquakes.