Interstory Drift Estimation of Nonlinear Structure Using Acceleration Measurement with Test Validation

Abstract

An interstory drift-estimation method using structural acceleration measurements is presented in this study. In this method, the structural system, generally modeled with multiple-degree-of-freedom (MDOF) and Bouc–Wen hysteretic models, is decomposed into a series of single-degree-of-freedom (SDOF) substructures for interstory drift prediction. A virtual linear structural model, representing the linear behavior of the designed substructure, is used to generate reference response signals to obtain the tracking error of acceleration. The tracking error of displacement is subsequently estimated with the implementation of a robust Kalman-filtering approach, and the corresponding interstory drift of the objective substructure is then predicted accordingly. The prediction performance of interstory drift, in terms of peak drift and time history, is numerically investigated with two SDOF models and a four-story shear-beam model adopting different hysteretic characteristics. Results obtained by the present numerical simulations for the illustrative examples are further validated by experimental investigations using a base-isolated three-story structure. The numerical simulation results are found to be in favorable correlation with some representative experimental data. Influences of the time interval of the tracking-error signals on the prediction performance is further studied and discussed.