Civil Engineering Reference
In-Depth Information
Figure 10.27
Time histories of measured and calculated displacement at building top
concrete, unconfined concrete and steel fibers, because the longitudinal steel in the boundary
elements at this level were confined with the stirrups. For the boundary elements at levels 2-6,
the section was composed of the unconfined concrete and steel fibers. The slabs at each floor
were also modeled as nonlinear beam-column elements with fiber sections.
The analysis procedure was separated into two steps, the static analysis and dynamic
analysis. In the first step, the gravity loads were applied to the building. It was assumed that
half the gravity load was supported by the web wall and the other half was taken by the gravity
columns. In the second step, the earthquake excitation was applied. Different damping ratios
were applied for the four test runs. The assumed damping ratios used for the runs EQ1-EQ4
were 2, 3, 6, and 8% respectively.
For simplicity, time histories of the predicted displacement at the top of the building for EQ3
and EQ4 are presented in Figure 10.27. The measured test data is also shown in the figures for
comparison. It can be seen from Figure 10.27 that the prediction of the displacement is close
to the measured results both in the vibration frequency and displacement magnitude.
