Get access
Advertisement

Model-based multi-metric control of uniaxial shake tables

Authors

  • Brian M. Phillips,

    Corresponding author
    1. Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA
    • Correspondence to: Brian M. Phillips, Department of Civil and Environmental Engineering, University of Maryland, 1173 Glenn L. Martin Hall, College Park, MD 20742, USA.

      E-mail: bphilli@umd.edu

    Search for more papers by this author
  • Nicholas E. Wierschem,

    1. Department of Civil and Environmental Engineering, University of Illinois, Urbana, IL, USA
    Search for more papers by this author
  • B. F. Spencer Jr.

    1. Department of Civil and Environmental Engineering, University of Illinois, Urbana, IL, USA
    Search for more papers by this author

SUMMARY

Shake tables provide a direct means by which to evaluate structural performance under earthquake excitation. Because the entire structure is mounted on the base plate and subjected to the ground motion in real time, dynamic effects and rate-dependent behavior can be accurately represented. Shake table control is not straightforward as the desired signal is an acceleration record, while most actuators operate in displacement feedback for stability. At the same time, the payload is typically large relative to the capacity of the actuator, leading to pronounced control-structure interaction. Through this interaction, the dynamics of the specimen influence the dynamics of the shake table, which can be problematic when specimens change behavior because of damage or other nonlinearities. Moreover, shake tables are themselves inherently nonlinear, making it difficult to accurately recreate a desired acceleration record over a broad range of amplitudes and frequencies. A model-based multi-metric shake table control strategy is proposed to improve tracking of the desired acceleration of a uniaxial shake table, remaining robust to nonlinearities including changes in specimen condition. The proposed strategy is verified for the shake table testing of both linear and nonlinear structures. Copyright © 2013 John Wiley & Sons, Ltd.

Get access to the full text of this article

Ancillary