Determination of Dynamic Soil Properties Using Geophysical Methods

The analysis of foundation vibrations and geotechnical earthquake engineering problems in civil engineering requires characterization of dynamic soil properties using geophysical methods. Dynamic structural analysis of the superstructures also requires knowledge of the dynamic response of the soilstructure, which, in turn relies on dynamics soil properties. Machine vibrations, blasting and seismic events are example so the type of dynamic input that an engineered systems may be subjected to. Geophysical methods are often used to characterize the dynamic soil properties of the subsurface. Field methods discussed in this section will focus on the low-strain tests that are not large enough to induce significant non-linear non-elastic stress strain behavior, they include: seismic refraction and reflection, suspension logging, steady-state vibration, down-hole, seismic cross-hole, spectral analysis of surface waves, and seismic CPT. Some reference is made of other non-geophysical tests used in geotechnical earthquake engineering that focus on the large-strain response of soils.