Advances in Real-Time Hybrid Testing Technology for Shaking Table Substructure Testing

Abstract

Shaking table substructure testing (STST) takes the substructure with complex behavior physically tested, with the behavior of the rest structural system being numerically simulated. This substructure testing allows the payload of a shaking table being fully utilized in testing of the most concerned part, thus significantly increases its loading capacity. The key to achieve a successful STST is to coordinate among the substructures, specifically, to satisfy compatibility, equilibrium, and synchronization at the boundary between numerical and experimental substructures. A number of studies have focused on the essential techniques of STST, and several applications have been carried out. Nonetheless, its progress is still in the preliminary stage, because of the limited applications using multi-directional shaking tables on large-scale specimens. This paper reviews a series of STSTs and their associated implementation aspects including hybrid testing frameworks, time integration algorithms, delay compensation methods, shaking table and actuator control schemes and boundary force measurement methods. The key techniques required for a successful test are also stressed, such as the force control of actuators to coordination among the substructures. Finally, challenges for future studies and applications are identified and presented.

Time history iteration algorithm for offline real‐time hybrid testing

“…The nonconvergent second half oscillates a lot and causes a large RMS error. In iteration 9, 𝐚 9 𝑁 and 𝐚 9 𝐸 were very similar and the iteration converged. As shown in Figure 9C, 𝐚 𝑝 𝑁 and 𝐚 𝑝 𝐸 converged to become perfectly identical in simulation.…”

“…The experimental substructure was subjected to high‐rate real‐time loading in RTHT, and its accurate dynamic response was obtained. Notably, RTHT can be conducted with servo‐hydraulic actuators, 7 shaking tables, 8 or a combination of the two 9 . To conduct RTHT, three problems must be properly addressed: (1) the computation of the numerical substructures should be efficient and stable; (2) the loading of the experimental substructure should be accurate and have low latency; (3) the communication between the substructures should be synchronized and have a small time delay.…”

Evaluation of data-driven NARX model based compensation for multi-axial real-time hybrid simulation benchmark study

“…With over 2 decades of dedicated research focusing on integration algorithms, delay compensation, and evaluation methods, RTHS has emerged as an effective and efficient technique for performance evaluation of systems under earthquakes. Its capability to facilitate real-time, large-scale testing has significantly contributed to the evaluation and validation of technologies for seismic hazard mitigation, marking a pivotal milestone in the field of earthquake engineering (Nakashima et al, 1992;Ou et al, 2015;Tian et al, 2020;Li et al, 2022;Palacio-Betancur and Soto, 2023).…”

Reproduction of seismic responses of wind turbine tower by hybrid tests considering shear and bending coupled boundary control

“…The lower part of the tower is subject to strong forces and moments and is more easily damaged during an earthquake or a period of high wind loads. However, testing the lower part of a tower in STST is difficult because of the complex dynamic force coordination on the boundary between numerical and physical substructures (Tian et al, 2020b). A hydraulic actuator is often employed to realize boundary compatibility between numerical and physical substructures.…”