Techno Press
You logged in as Techno Press

Geomechanics and Engineering
  Volume 14, Number 2, February10 2018 , pages 161-174
DOI: https://doi.org/10.12989/gae.2018.14.2.161
 


SSI effects on seismic behavior of smart base-isolated structures
Saeed Shourestani, Fazlollah Soltani, Mojtaba Ghasemi and Sadegh Etedali

 
Abstract
    The present study investigates the soil-structure interaction (SSI) effects on the seismic performance of smart base-isolated structures. The adopted control algorithm for tuning the control force plays a key role in successful implementation of such structures; however, in most studied carried out in the literature, these algorithms are designed without considering the SSI effect. Considering the SSI effects, a linear quadratic regulator (LQR) controller is employed to seismic control of a smart base-isolated structure. A particle swarm optimization (PSO) algorithm is used to tune the gain matrix of the controller in both cases without and with SSI effects. In order to conduct a parametric study, three types of soil, three well-known earthquakes and a vast range of period of the superstructure are considered for assessment the SSI effects on seismic control process of the smart-base isolated structure. The adopted controller is able to make a significant reduction in base displacement. However, any attempt to decrease the maximum base displacement results in slight increasing in superstructure accelerations. The maximum and RMS base displacements of the smart base-isolated structures in the case of considering SSI effects are more than the corresponding responses in the case of ignoring SSI effects. Overall, it is also observed that the maximum and RMS base displacements of the structure are increased by increasing the natural period of the superstructure. Furthermore, it can be concluded that the maximum and RMS superstructure accelerations are significant influenced by the frequency content of earthquake excitations and the natural frequency of the superstructure. The results show that the design of the controller is very influenced by the SSI effects. In addition, the simulation results demonstrate that the ignoring the SSI effect provides an unfavorable control system, which may lead to decline in the seismic performance of the smart-base isolated structure including the SSI effects.
 
Key Words
    base isolation; soil-structure interaction; smart base-isolated structures; LQR controller; particle swarm optimization algorithm
 
Address
Saeed Shourestani, Fazlollah Soltani and Mojtaba Ghasemi: Department of Civil and Surveying Engineering, Graduate University of Advanced Technology, Kerman, Iran

Sadegh Etedali: Department of Civil Engineering, Birjand University of Technology, Birjand, Iran
 

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2022 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: info@techno-press.com