A falling-weight impactor with a controlled force energy spectrum was used
to generate surface waves in soft clay soil. Field measurements of both Loa
d and response in terms of vertical acceleration were made. The acceleratio
n-type frequency response function (FRF) between the point of source and th
e point of response was established. The Rayleigh wave velocity of the soil
was estimated from the measured acceleration time histories and from the e
stablished FRFs, Simulations of the field measurements were conducted and t
he dynamic response of the soil was studied in terms of the vertical accele
ration and displacement at the soil surface. Two-dimensional numerical resu
lts were scaled to three dimensions. The effect of incorporating contributi
ons from shear waves and compression waves at the surface was demonstrated,
FRFs based on simulated data were established. The scaled numerical result
s and measured values are in good agreement.