Substructure shake table test method using a controlled mass: formulation and numerical simulation

Abstract

SUMMARY This study proposes a new substructure shake table test method that allows for experimental investigation of the lower portion of structures while the upper part is numerically analyzed. Compatibility conditions are derived to ensure that the dynamic characteristics of the substructured system are equivalent to the reference entire structure. This method utilizes controlled masses to incorporate interface forces from the computational substructure to the experimental substructure. A feasible implementation procedure for the interface force compatibility is developed using a series of conversions and signal processing. For validation of the capabilities and limitations of the proposed substructure method, numerical simulations are performed using detailed models including dynamics of the controlled mass systems. Results from the numerical simulations showed that the proposed substructure method produced comparable results to the reference entire simulations. The average error between top floor displacements produced by substructured and entire responses for earthquake inputs was 7.1%. Numerical studies showed that the substructure method has potential to serve as an alternative to shaking table tests of entire structures. Copyright © 2012 John Wiley & Sons, Ltd.

Real‐time hybrid simulation of semi‐active control using shaking table: Proposal and verification of a testing method for mid‐story isolated buildings

“…The study was conducted based on the estimation with the correlation coefficient q and the RMS ratio (RMS of the reproduced value/RMS of the commanded (target) value. The correlation coefficient q and the RMS are defined by Equations (14) and (15), respectively:…”

Seismic performance evaluation of high voltage disconnect switches using real‐time hybrid simulation: I. System development and validation

“… used a shaking table together with dynamic actuators, where analytical substructures were modeled on top and bottom of the experimental substructure. Recently, Nakata and Stehman proposed a method that allows modeling of an analytical substructure on top of an experimental substructure, which is tested on a shaking table. In the coming years, an increase in RTHS applications on shaking tables is expected, especially with the development of shaking table arrays in various laboratories around the world, such as Tongji University, Shanghai, China, or the NEES facilities at the University of Nevada, Reno.…”

Substructure Shake Table Testing with Force Controlled Actuators

“…These tests required both displacement and force dependent boundary conditions: a shake table satisfied the displacement boundary condition while the force condition was supplied using a displacement feedback actuator. Nakata and Stehman (2012) expanded on this technique where inertial masses were used to impose the computational force on the experimental substructure.…”