Performance-based seismic design framework for inertia-sensitive nonstructural components in base-isolated buildings

Abstract

Damage to building structural systems during earthquakes has led to significant downtime and economic losses, and, in some cases, to demolition of the buildings themselves. Failure of nonstructural components have also been a major contributor to the economic losses and are known to have threatened the lives of building inhabitants. As a result, investigations in many regions in the world that have experienced strong shaking causing damage to buildings have opted to incorporate base isolation as an earthquake protection measure. As base isolation of buildings becomes more widespread, especially for hospitals, emergency centers, and other buildings with critical functions and/or valuable contents, it is necessary to ensure nonstructural components within these buildings are appropriately designed and detailed. Currently, the design of the fastenings of critical nonstructural components in base-isolated buildings is performed using prescriptive code requirements developed for conventional fixed-based buildings that have entirely different dynamics. This paper describes a performance-based seismic design framework for developing design equations for nonstructural components within base-isolated buildings. The framework utilizes displacement damage limit-states of the components to determine the design lateral force. An example of how to apply the framework is illustrated via a case study that combines experimental structural responses recorded during the shake table testing of a base-isolated building with simulated nonlinear nonstructural component responses.