Seismic flat dilatometer tests in Piedmont residual soils

A hybrid test combining the conventional flat dilatometer with downhole geophysical testing has been developed and referred to as the seismic flat dilatometer test (SDMT). Downhole seismic velocity measurements have been incorporated with a flat dilatometer by placing a velocity transducer in a connecting rod just above the blade. The seismic dilatometer test has the exceptional advantages of determining both estimates of soil properties and stratigraphic information, while also measuring the shear wave velocity (V-s) within a single sounding. The hybrid test is rapid, simple, and cost-effective requiring essentially no more time than a conventional dilatometer sounding. The seismic dilatometer was field tested in the Piedmont residual soils of eastern Alabama with the shear wave velocity results compared with adjacent seismic piezocone profiles, crosshole geophysical arrays, and spectral analysis of surface waves (SASW).