ABSTRACT
The problem of the response spectral density evaluation for vibrational system with random and time-independent parameters under stationary random loading is stated and solved. The loading and random parameters are supposed to be independent. The closed-form equations are obtained for both spectral density and mean square value in case of single-degree-of-freedom system with uniformly distributed stiffness. It is shown that it is possible to consider soil elasticity modulus as a random variable with lognormal distribution; the distribution parameters are evaluated. Spectral densities were calculated for response of machine foundations with random dynamic loads (grinding mills) and for transportation tunnels together with surrounding soil.
