Soil dynamics and earthquake engineering

The term soil has originated from the latin word solum which has different meanings. Soil dynamics deals with the study of material properties of soil under dynamic stress. Knowledge of classical dynamics of elastic continuum and dynamics of vibrations are required for the effective soil dynamics study. Since soils and rocks are naturally occurring materials, it is always preferred to have test on theses before use. Relying fully on structural handbook is not advisable. Earth quake motion dynamics is usually expressed in terms of acceleration – time trace, velocity-time trace and displacement-time trace. There exist two methods for the evaluation of soils- deterministic and non-deterministic. Since the soil dynamics and earth quake engineering are very much inter related, it lead to the emergence of new branch of engineering- geotechnical earthquake engineering. In majority of the cases, motion of the soil causes earthquakes. The motion of the soil is transmitted to the structure leading to damages. In seismic zone, study of the motion of soil or soil dynamics is very significant and for any earthquake resistant design of structures, seismic data plays a major role.