Shake table real‐time hybrid simulation techniques for the performance evaluation of buildings with inter‐story isolation

Abstract

Summary Interstory isolation systems have recently gained popularity as an alternative for seismic protection, especially in densely populated areas. In inter‐story isolation, the isolation system is incorporated between stories instead of the base of the structure. Installing inter‐story isolation is simple, inexpensive, and disruption free in retrofit applications. Benefits include nominally independent structural systems where the accelerations of the added floors are reduced when compared to a conventional structural system. Furthermore, the base shear demand on the total structure is not significantly increased. Practical applications of inter‐story isolation have appeared in the United States, Japan, and China, and likewise new design validation techniques are needed to parallel growing interest. Real‐time hybrid simulation (RTHS) offers an alternative to investigate the performance of buildings with inter‐story isolation. Shake tables, standard equipment in many laboratories, are capable of providing the interface boundary conditions necessary for this application of RTHS. The substructure below the isolation layer can be simulated numerically while the superstructure above the isolation layer can be tested experimentally. This configuration provides a high‐fidelity representation of the nonlinearities in the isolation layer, including any supplemental damping devices. This research investigates the seismic performance of a 14‐story building with inter‐story isolation. A model‐based acceleration‐tracking approach is adopted to control the shake table, exhibiting good offline and online acceleration tracking performance. The proposed methods demonstrate that RTHS is an accurate and reliable means to investigate buildings with inter‐story isolation, including new configurations and supplemental control approaches.

A simple strategy for dynamic substructuring: I. Concept and development

“…Carrion and Spencer 30 adopted a modelbased approach and used an inverse dynamics compensation procedure. This method was combined with the online delay estimation procedure of Darby et al 28 into an integrated compensation method by Liu et al 31 An inverse compensation approach has also been also used 32,33 in the context of substructuring with a shake table. In these cases, the inverse was of the model of the actuator/shake table together with the PS.…”

Real-time hybrid testing of a structure with a piezoelectric friction controllable mass damper by using a shake table

“…As mentioned above, the control time delay of the shake table may cause deviation of the experimental results. To alleviate this problem, a long‐period primary structure, which has a smaller impact of time delay in the RTHT‐ST, and a commonly used shaking table controller (PID controller) are utilized in both tests. The controller has an inner feedback control loop continuously correcting the error e ( t ) between the desired and measured table displacement.…”

Basic examination of two substructuring schemes for shake table tests

“…Dynamical substructuring by simply using actuators is a well‐studied technique. However, its application to shake table tests remains under development . A distinct feature of shake table tests is that the table dynamics is significantly affected by a specimen on the table, e.g.…”