A Method to Predict Strength Requirements for Non-Structural Elements Permitted to Develop Nonlinear Response

The required strength of non-structural elements that are permitted to develop nonlinear behavior can be far lower than the strength required to maintain elastic response. This work quantifies this difference using nonlinear floor response spectra from New Zealand instrumented buildings. This informs extensions to a recent method for predicting elastic floor spectra using structural modal characteristics. The updated method further includes the effects of structural inelasticity using results from numerical modelling. This novel prediction approach provides greater accuracy than current practices without compromising simplicity. The method offers design options that could limit costs associated with seismic losses and bracing requirements.