Base Isolation Systems Employing Variable Friction Dampers Based on a STFT Controller

Abstract:

Conventional isolation systems may induce an excessive response in near-fault earthquakes. A new short time Fourier transformation (STFT) control algorithm for variable friction dampers (VFD) is developed to improve the performance of base isolation buildings in near-fault earthquakes. The STFT controller varies the clamping force in the VFD damper to achieve the response reduction. In addition, the STFT algorithm is implemented analytically on a multi degree of freedom system (MDOF) with laminated rubber bearings and variable friction dampers in Simulink environment. Three types of earthquakes representing a wide variety of ground motions are considered as the ground excitations in the simulation. The numerical show that, compared with conventional isolation systems, the semi-active isolation system controlled by the STFT algorithm can reduce the excessive response in near-fault earthquakes effectively.

• Periodical: Applied Mechanics and Materials (Volumes 90-93)
• Pages: 1566-1575
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.90-93.1566
• Online since: September 2011
• Authors: Zi Shu Dai
• Keywords: Base-Isolation, Near-Fault Earthquake, Short Time Fourier Transformation, Simulink, Variable Friction Damper

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