This page last updated August 18, 1999

A building in Burbank, California has been instrumented by the

California Strong Motion Instrumentation Program. 

It is designated as Building 24370.

I have analyzed it on SAP2000 to allow for better understanding of the time history behavior.

The buttons will direct you to a floor plan of the steel framing, and an elevation view of the perimeter wall frames.

In addition, you can see the response to the Northridge Newhall ground motion.   The 3D view takes about 30 minutes to download (not recommended for surfers!).   The 2D view takes about 15 minutes to download.

Learning Objective

After reviewing these pages, the student will be able to:

1. visualize the motion of a building during an earthquake.
2. describe how the motion changes from erratic to harmonic as the earthquake progresses.
3. recognize that the harmonic motion is similar to the fundamental mode of vibration of a structure.

Note that as the earthquake begins, the motion is very erratic, but the lateral motion of the building is not so large.  As the building gains in internal energy, and the ground motion begins to subside, the lateral movement of the building becomes very smooth, and begins to simulate Simple Harmonic Motion of the fundamental period of vibration.

References: