Determination of SASW Shear-Wave Velocity Along a Segment of Interstate 70 in St. Louis, Missouri

The University of Missouri, Rolla acquired multi-channel surface-wave (Rayleigh wave) seismic control along a 6400 ft segment of Interstate I-70, in downtown St. Louis, Missouri. The acquired surface wave data set was processed (multi-channel analysis of surface waves; MASW) and transformed into a 2-D MASW shear-wave velocity profile with a lateral station spacing of 40 ft. The 2-D MASW profile extends from the surface to a depth of 50 ft. The interpreted depth to acoustic bedrock along the length of the 2-D profile varies between 20 ft and 44 ft. The interpreted 2-D MASW shear-wave velocity profile was compared to available bedrock (borehole) and seismic cone penetrometer (SCPT) control provided by the Missouri Department of Transportation (MoDOT). The geotechnical data provided by MoDOT and presented herein indicate the interpreted 2-D MASW shear-wave velocity profile correlates well with available bedrock and SCPT control, supporting the conclusion that the MASW technique can be used to generate reliable 2-D shear-wave velocity profiles of the shallow subsurface.