RANDOM VIBRATION ANALYSIS OF MULTI-DEGREE-OF-FREEDOM STRUCTURES WITH HYSTERETIC CHARACTERISTICS SUBJECTED TO COMBINED RANDOM LOADS

A method to estimate the stochastic response of hysteretic structures under combined random loads regarded as Gaussian white noise is invest igated. The response statistical moments of structures, with hystereti c characteristics approximated by Wen's mathematical model, are obtain ed by using the Fokker-Planck equation method with a cumulant truncati on technique. This paper deals with the formulation for the multi-degr ee-af-freedom system, and demonstrates that resulting variances of the response for a three-degree-of-freedom structure, as a numerical exam ple, agree well with a Monte Carlo simulation.