Estimating Field Properties of Soft Soil Using Penetration-Type S-Wave Probe

A new s-wave probe, called "MudFork", has been recently developed and is used in accurate measurements of shear wave velocities of soft soils. The probe is composed of two bender elements mounted on a "fork" having two blades, one element perturbing ground and the other one monitoring seismic waves, and can be penetrated using SPT(standard penetration test) rods pushed with a routine boring machine. To expand its use to estimate undrained shear strength and density, an attempt to correlate shear wave velocity to those properties was made at normally consolidated silt near Incheon, Korea. A simple linear relationship between shear strength and shear wave velocity was obtained, and a tentative relationship between density and shear wave velocity was also defined.