Reliability Assessment of Real-time Hybrid Simulation Under Worst-Case Scenarios Using Frequency-Domain Evaluation Indices

Abstract

Real-time hybrid simulation (RTHS) allows researchers to physically evaluate critical parts of a prototype structure at full scale in the laboratory while the rest is numerically modeled. The reliability of the RTHS experimental results however still remains unsolved in the presence of experimental errors even though a number of methods have been proposed based on the actuator tracking in the time domain. Frequency-domain evaluation indices (FEI) provide a novel and effective technique to evaluate the amplitude and phase errors of the actuator tracking. In this paper, the correlation between the reliability of RTHS results and the FEI indices is explored for the worst-case scenarios of single-degree-of-freedom (SDOF) linear elastic structures. The influence of natural frequency and damping ratio are considered through a suite of ground motions. The relationship between the FEI parameters and the error of RTHS replicating actual structural response is explored and a criterion based on worst-case scenarios is proposed for reliability assessment. Numerical simulations are conducted to demonstrate the effectiveness of the proposed reliability criterion.