ABSTRACT
The primary sources of oscillations include the operation of permanent unbalanced machinery and equipment, the movement of different kinds of transportation means, mechanized construction of civil engineering works, blasting, seismic activities, wind gusts, and wave impact. A pulsed source of oscillations causes longitudinal waves in soil and rock, these vibrations being associated with oscillations of soil particles in the direction of wave propagation; and transverse waves or shear waves, in which soil particles move normally to the direction of wave propagation. The quality of soil can be improved so as to provide an appropriate stability under dynamic loading of an expected intensity. A footing should provide a reliable bedplate for machinery so as to secure its normal performance, and reduce noise in the form of unacceptable structural vibration of the building and its neighbourhood. The inclusion of seismic effects is mostly reflected in the design of retaining walls and basements.
