Vibrations Caused by Pile Driving

Ground vibrations caused by impact were measured at two sites; one consisting of sand and the other of clay. Measurements were made at various radial distances from the impact location. The impact was produced by a weight falling either on to a plate or on to a rod partly driven into the ground, the latter case simulating pile driving on a small scale. When expressed in terms of scaled energy, the measured peak particle velocities were in reasonable agreement with some of the published data for clay sites but the agreement was poorer for sand sites. Several theoretical expressions were developed for peak particle velocity for both body and Rayleigh waves. All of these expressions yielded calculated velocities that were considerably greater than the values observed. It is considered that at least some of the disagreement could be attributed to energy losses.