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A landmark experimental program was conducted to advance the understanding of nonstructural system performance during earthquakes. The centerpiece of this effort involved shake table testing a full-scale five-story reinforced concrete building furnished with a broad variety of nonstructural components and systems (NCSs) including complete and operable egress, mechanical and electrical systems, facades, and architectural layouts. The building-NCS system was subjected to a suite of earthquake motions of increasing intensity, while base-isolated and then fixed at its base. In this paper, the major components of the test specimen, including the structure and its NCSs, the monitoring systems, and the seismic test protocol are described in detail. Important response and damage characteristics of the structure are also presented. A companion paper describes the damage observed for the various NCSs and correlates these observations with the structure's response.

Summary This paper presents a novel nonlinear finite element (FE) model updating framework, in which advanced nonlinear structural FE modeling and analysis techniques are used jointly with the extended Kalman filter (EKF) to estimate time‐invariant parameters associated to the nonlinear material constitutive models used in the FE model of the structural system of interest. The EKF as a parameter estimation tool requires the computation of structural FE response sensitivities (total partial derivatives) with respect to the material parameters to be estimated. Employing the direct differentiation method, which is a well‐established procedure for FE response sensitivity analysis, facilitates the application of the EKF in the parameter estimation problem. To verify the proposed nonlinear FE model updating framework, two proof‐of‐concept examples are presented. For each example, the FE‐simulated response of a realistic prototype structure to a set of earthquake ground motions of varying intensity is polluted with artificial measurement noise and used as structural response measurement to estimate the assumed unknown material parameters using the proposed nonlinear FE model updating framework. The first example consists of a cantilever steel bridge column with three unknown material parameters, while a three‐story three‐bay moment resisting steel frame with six unknown material parameters is used as second example. Both examples demonstrate the excellent performance of the proposed parameter estimation framework even in the presence of high measurement noise. Copyright © 2015 John Wiley & Sons, Ltd.