What Does Spectral Analysis of Surface Waves (SASW) Mean?
Spectral analysis of surface waves (SASW) is a non-destructive method of testing the shear wave velocity profile of soil and rock. Surface waves have a dispersive characteristic that is useful in determining shear wave velocity variation or stiffness of the soil layers with depth.
SASW can be used for depths greater than 150 feet provided the accessible area on the ground surface has a length greater than or equal to the measurement depth required.
Trenchlesspedia Explains Spectral Analysis of Surface Waves (SASW)
SASW tests are useful in determining soil layer profiles including their depth, velocity and condition of the layers. In the SASW method, Rayleigh waves are generated on the ground using hammer impact. The waves are picked up by two receivers placed on the surface and forward and reverse configurations are used to generate SASW profiles.
Receivers placed at short intervals are used to shallow layers, while receivers placed at longer intervals are used to sample greater depths. The accessible surface at the investigation site limits the depth to which the test can be conducted.