Dynamic Analysis of Thirteen‐Story Building

Abstract

The results from dynamic analyses by computer of an existing 13‐story steel moment resisting frame building are presented. The computed dynamic properties and response behaviors are compared to the true values as determined from the recorded motions in the building during two actual earthquakes. It is shown that state‐of‐practice design type analytical models can predict the actual dynamic properties. The influence of various modeling features on the computed seismic responses is demonstrated via sample response spectrum analyses using the SEAOC spectrum. The actual building time‐history seismic response exhibited amplitude modulation, which is shown to be caused by coupled modes having closely spaced periods. It is shown that design‐type analytical models can reasonably capture the true seismic response of the study building provided the excitation levels are such that the building responds primarily in a linear‐elastic manner.