Stability Anaysis of Real-time Hybrid Simulation for a Multi-story Structure Considering Time-delay of Hydrolic Actuator

Real-time hybrid simulation (RTHS) is a kind of simulation where an experimental component of a structure is tested within a numerical model describing the remainder of the system. In this paper, a multi-story structure is partitioned into numerical and experimental substructures, and vibration behavior of the experimental stories are evaluated within the real-time simulation of the rest of the system. An electro-hydraulic actuator is employed to apply static and inertial forces to the experimental structure due to the forces calculated by the numerical substructure. An actuator dynamic is approximated by a pure time-delay, and the time-delay in the closed loop of simulation may causes inaccuracy results or even instability. Thus, the approach of delay differential equation (DDE) modelling is used to determine the dependence of the critical delay on the parameters of the system. The results demonstrate the influence of non-dimensional parameters and partitioning effects in stability of the hybrid simulation.