Krystyna Mazur-Śniady

Dynamic response of linear structures to random streams of arbitrary impulses in time and space

The dynamic response of continuous structures to a stream of arbitrary impulses is considered. The impulses commence at random times and are located at random points on the surface of the structure. The shapes of the impulses can be arbitrary and can have a deterministic or stochastic nature, both in time and in space. The respective time durations and amplitudes of the impulses are also random. An analytical technique is developed to determine the response of the structure, and explicit expressions are provided for the expected value and covariance of the structure deflection. The results presented in the work can be used, for example, in estimating the reliability of bridge loading by traffic flow.

Fuzzy Stochastic Vibrations of Double-Beam Complex System as Model Sandwich Beam with Uncertain Parameters

The dynamic behavior of a double Euler-Bernoulli beam system with uncertain parameters (fuzzy random variables) under a fuzzy stochastic excitation and axial compression is being considered. The beams are identical and parallel, one is above the other, and they are continuously coupled by a linear two-parameter (Pasternak subsoil) elastic element. This double Euler-Bernoulli beam system can be also treated as a theoretical model of a sandwich beam. The load process is fuzzy random both in space and time. The top beam carries a fuzzy stochastic load. The solution of the problem was found thanks to the fuzzy random dynamic influence function. The aim of the paper is to find the solution for the membership function of the probabilistic characteristics of the response of the structure.