This field trip consists of stops in four locations (Fig. 1) that provide insight into the seismic retrofit and strong motion instrumentation of the Golden Gate Bridge ((Figs. 2) and 3). Only one of the four stops is normally open to the public (Stop 3a). The first stop at the Golden Gate Bridge Highway and Transportation District (GGBHTD) office board room will include an introduction to the bridge history and presentation of the seismic retrofit schemes, strong motion instrumentation of the bridge, and the data products available from the California Strong Motion Instrumentation Program (CSMIP) of the California Geological Survey (CGS). At the second stop, participants will see a free-field instrument in the maintenance area.

At the third stop, we will observe retrofit work under way (in 2006) from a public overlook area. At the fourth stop, we will see the seismic sensors and instrumentation installed on the bridge. The locations of these four stops (Stops 1, 2, 3a, and 3b) are shown in Figure 4.