Comparing Seismic Performance of Steel Structures Equipped with Viscous Dampers and Lead Rubber Bearing Base Isolation under Near-Field Earthquake
Abstract: In the present
research, seismic behaviours of a steel frame equipped with either viscous
damper or lead-core rubber bearings (LRB) isolator were evaluated and compared
under the effect of near-fault earthquake records. For this purpose, three
buildings of 5, 10, and 15 stories equipped with lateral bearing systems
composed of steel moment-resisting frames were subjected to 7 near-fault
earthquake accelerogram pairs at earthquake hazard levels 1 and 2, so as to
evaluate their responses under three scenarios, namely without any energy
dissipation system, with viscous damper, and with LRB isolator, using dynamic
analysis of time history utilizing PERFORM 3D v5 software. The results were
indicative of enhancement in seismic performance of the viscous damper-equipped
structures at earthquake hazard level 1, as the corresponding performance level
was enhanced from life safety to uninterrupted usability, while no significant
seismic performance level enhancement was determined at seismic level 2.
Seismic isolator-equipped structures were also associated with seismic
performance level enhancement from life safety to uninterrupted usability at
both earthquake hazard levels. Relative lateral displacement at floor levels in
damper-equipped structures and seismic isolator-installed buildings were found
to be about 29% and 68% improved over that of the structure with no energy
dissipation system. Results of distribution of shear forces within structures
equipped with viscous damper and seismic isolator, as compared against that of
the structures with no energy dissipation system, indicted increased and
decreased shear forces, respectively..
Author: Mohammad Ganji,
Hossein Kazem
Journal Code: jptsipilgg170023
