Various techniques for vibration reduction were investigated with primary emphasis given to dynamic vibration absorbers and isolators as well as to interlayers of loose rock induced by explosion. In the former case, modern vibration theory was used for the development of new, modified devices, while for the latter the effectiveness of shielding was investigated on the basis of experimental results.
Dynamic photoelasticity techniques were applied to study wave propagation phenomena. The data obtained testify that this technique may be used for modelling engineering problems. The method was used to study the efficiency of shields with respect to vibration reduction in the form of interlayers of finite depth placed near the free surface. Shields of various depths perpendicular or inclined have been studied for various positions of an impulsive source within the medium. The results demonstrate the dependence of shield efficiency on the source characteristic, the location of the protected object relative to the source and the wave type.
Novel vibration isolators were analysed possessing vertical as well as horizontal pliability which results from the bending of plates. Dynamic vibration absorbers were analysed and the associated problems of the bending theory of plates stretched or compressed in their middle plane were examined. A method for the evaluation of resistant building frames based on an energy approach was made for the correlation of the (ir)regularity index to the ductility factor. Responses of masonry structures under bad soil conditions have also been investigated. Analytical methods for determining influence functions in the time domain are presented for a homogeneous, elastic half-space allowing the decomposition of the total wave field into surface and body waves. Impedance functions for rigid rectangular foundations as well as the cross-interaction effects between two rigid foundations resting on inhomogeneous soil and layered soil were determined by semianalytical and numerical techniques.