3D Full Waveform Inversion Test Conducted at the Construction Site of the New Washington State Convention Center Building Located in Downtown Seattle, WA

Results of 3-D full waveform tomography to develop a 3-D map of Go is shown in this experiment. This 3D Full Waveform Inversion study utilized 48 4.5 Hz geophones. The sensors were laid out in a 4-by-12 10-ft spacing grid. Thumper was used as a vibrational source at a total of 65 shaker points in a 5-by-13 grid. An 8 to 80 Hz 12 seconds chirp forcing function was applied at each shaker location. The time-domain 3D Gauss-Newton FWI method developed by Co-PI Tran and his research group was used to determine the 3D velocity model of the test region. Results from this experiment can be used as design reference of nearby structures and for future studies on ground deformations due to excavations.