Probability density function of MDOF structural systems under non-normal delta-correlated inputs

A method to approximate the probability density function of MDOF linear sys tems under non-normal delta-correlated input is presented. The method requi res: (i) the evaluation of the response cumulants up a given order, by solv ing the set of cumulant differential equations; (ii) the evaluation of the quasi-moments of the response by means of recursive relationships, once the response cumulants are known; (iii) the evaluation of the coefficients of the C-type Gram-Charlier series expansion of the response probability densi ty function, by solving a set of linear algebraic equations, whose known te rms depend on the quasi-moments of the response up to a given order. The nu merical application shows the versatility and the accuracy of the proposed method. (C) 1999 Elsevier Science S.A. All rights reserved.