A substructure shaking table test for reproduction of earthquake responses of high‐rise buildings

Abstract

SUMMARYWhen subjected to long-period ground motions, high-rise buildings' upper floors undergo large responses. Furniture and nonstructural components are susceptible to significant damage in such events. This paper proposes a full-scale substructure shaking table test to reproduce large floor responses of high-rise buildings. The response at the top floor of a virtual 30-story building model subjected to a synthesized long-period ground motion is taken as a target wave for reproduction. Since a shaking table has difficulties in directly reproducing such large responses due to various capacity limitations, a rubber-and-mass system is proposed to amplify the table motion. To achieve an accurate reproduction of the floor responses, a control algorithm called the open-loop inverse dynamics compensation via simulation (IDCS) algorithm is used to generate a special input wave for the shaking table. To implement the IDCS algorithm, the model matching method and the H ∞ method are adopted to construct the controller. A numerical example is presented to illustrate the open-loop IDCS algorithm and compare the performance of different methods of controller design. A series of full-scale substructure shaking table tests are conducted in E-Defense to verify the effectiveness of the proposed method and examine the seismic behavior of furniture. The test results demonstrate that the rubber-and-mass system is capable of amplifying the table motion by a factor of about 3.5 for the maximum velocity and displacement, and the substructure shaking table test can reproduce the large floor responses for a few minutes.

Effects of Equipment-Structure-Soil Interaction on Seismic Response of Equipment and Structure via Real-Time Dynamic Substructuring Shaking Table Testing

“…Further studies [27,28] have corroborated that this scheme application allowed one to avoid interference from noise and other interfering signals from the external sources and verified its effectiveness through the practical application to nonlinear control. Guo et al [29] further explored a strategy for inverse dynamics compensation and developed a new control methodology called fullstate compensation via simulation (FSCS).…”

A shaking table real-time substructure experiment of an equipment–structure–soil interaction system

“…Based on this conception, inverse dynamic compensation via simulation (IDCS) [29][30][31] is developed and used to control nonlinear systems without the effect of external noise. IDCS controller proves to be efficient and guarantees good performances.…”

On the assessment of passive devices for structural control via real-time dynamic substructuring

“…Figure 5(b) shows the stability region for fixed p = 2 using the curves defined parametrically by equations (13), (14) and (15). Considering the lightly damped systems commonly studied in civil engineering applications (ζ < 0.1), the curveτ 2 with n = 1 can be used as the practical stability boundary because encloses the others theoretical boundaries into the unstable region.…”

“…Also, we supposed a nonlinear viscous fluid damper added to the system with exponent α=0.15 and a nonlinear coefficient c d =50kN(sec/m) 0. 15 . Figure 8a shows the trajectories for a SDOF system with an added delayed friction damper (α=0 and p s =2.0); whilst Figure 8b shows the trajectories considering a SDOF system with the added delayed nonlinear fluid viscous damper (α=0.15 and p n =2.03).…”