Numerical and experimental studies of linear systems subjected to non-Gaussian random excitations

This paper presents a numerical simulation scheme for generating symmetric non-Gaussian random processes governed by prescribed kurtosis and spectral density. The generated process is represented as a continuous stationary ra ndom signal with occasional spikes super imposed on a Gaussian random backg round. The generated time history data records are used to simulate random excitations acting on Linear single-degree-of-freedom systems. The results of the numerical simulation are compared with those measured experimentally . For a wide band random excitation with kurtosis close to 3, the response kurtosis is found to be very sensitive to small changes in the excitation k urtosis. This is manifested by the appearance of significant spikes in the time history records when the excitation records do not display any signifi cant spikes. The influence of the system damping is also examined for narro w-band and wide-band random excitations, and some differences are reported in the results. (C) 1998 Elsevier Science Ltd. All rights reserved.