Quantifying the Errors of Dynamic Displacement Testing: An Alternative Method for Seismic Simulation Testing of Columns

This paper studies a dynamic testing method called dynamic displacement testing (DDT). Similar procedures to this method have been used in the past to perform experimental testing; however, the procedure was never acknowledged as a specific testing method, and therefore, its errors have never been investigated. The method analyzes the finite-element (FE) model of a structure under dynamic base excitation and applies the obtained displacement time history to the specimen in the laboratory. Sensitivity analyses using 3D continuum (representing the actual specimen) and 2D macro FE models are performed on steel and reinforced concrete bridge pier case studies to detect and quantify significant sources of error associated with this method. Furthermore, 500 Monte Carlo simulations are performed for each case study to assess the variability of the responses. It is shown that the method could apply 30% and 18% errors into displacement and energy dissipation responses, respectively. However, calibrating the FE models at material and element levels could significantly increase the accuracy and precision of the method.