كليدواژه :
Hysteretic behavior , See-Saw Motion , Finite element analysis , Repairable Buildings
چكيده فارسي :
Design of repairable buildings, whose structural systems can be easily repaired after a major
earthquake, instead of demolishing and rebuilding, havebeen paid great attention by some researchers in
recent decade.In this paper a study in which specific attention has been paid to the behavior of the central
support which has a main role in creating the possibility of seesaw motion in the building’s structural system,
as well as creating some capacity of seismic energy dissipation is presented.The proposed device can be
called briefly Yielding Curved Bars (YCB) energy dissipater. The YCB energy dissipater can act as the
central support under the central main column of the building at lowest level. The clipped hemisphere carries
the vertical load of the central column of the building with seesaw motion, and transfer it directly to its
concave bed, while the curved bars around the clipped hemisphere act as yielding elements during the
seesaw motion of the building which causes the central column to incline, and this inclination causes the
rotation of the YCB device around a horizontal axis, resulting in large plastic deformations of curved rods,
and therefore, large amount of energy dissipation during earthquake excitations. The YCB device was
modeled by a powerful finite element analysis computer program and its hysteretic behavior under the
simultaneous effects of vertical and horizontal loads was obtained. To investigate the efficiency of using the
YCB device in reduction of seismic response of buildings a multi-story regular steel building was considered
once with conventional design and once equipped with the YCB device and some similar yielding energy
dissipaters under all circumferential columns and the seismic responses were calculated by time history
analyses, employing a set of selected three-component accelerograms. Resultsshow the high efficiency of the
YCB devices in seismic response reduction of buildings.
