Reduction of Structural Response to Near Fault Earthquakes by Seismic Isolation Columns and Variable Friction Dampers

This paper will focus on the investigation of a hybrid seismic isolation system with passive variable friction dampers for protection of structures against near fault earthquakes. The seismic isolation can be implemented by replacing the conventional columns fixed to the foundations by seismic isolating ones. These columns allow horizontal displacement between the superstructure and the foundations and decouple the building from the damaging earthquake motion. As a result, the forces in the structural elements decrease and damage that may be caused to the building by the earthquake significantly decreases. However, this positive effect is achieved on account of displacements occurring in the isolating columns. These displacements become very large when the structure is subjected to a strong earthquake. In this case, impact may occur between the parts of the isolating column yielding their damage or collapse. In order to limit the displacements in the isolating columns, it is proposed to add variable friction dampers. A method for selecting the dampers’ properties is proposed. It is carried out using an artificial ground motion record and optimal active control algorithm. Numerical simulation of a seven-story structure shows that the proposed method allows efficient reduction in structural response and limits the displacements at the seismic isolating columns.

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  • English

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  • Accession Number: 01154408
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 7 2010 11:04AM