Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient

For real-time dynamic substructure testing (RTDST), the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated. Therefore, this study proposes to investigate the stability and accuracy of the central difference method (CDM) for RTDST considering the specimen mass participation coefficient. First, the theory of the CDM for RTDST is presented. Next, the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are investigated. Finally, numerical simulations and experimental tests are conducted for verifying the effectiveness of the method. The study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen, and the stability limit first increases and then decreases as the mass participation coefficient increases. In most cases, the mass participation coefficient will increase the stability limit of the algorithm, but in specific circumstances, the algorithm may lose its stability. The stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper.