PREDICTION OF EXTREME RESPONSE OF NONLINEAR STRUCTURES BY EXTENDED STOCHASTIC LINEARIZATION

The paper describes stochastic linearization methods that are specific ally designed for the purpose of predicting extreme responses. Standar d stochastic linearization applied to a nonlinear dynamic system is ba sed on a mean square deviation measure to derive the 'equivalent' line ar system. Experience indicates that the obtained linear system may ha ve approximately the same mean square response as the original nonline ar system. For predicting extreme response this procedure is not, howe ver, equally suitable. In the case of, e.g. strong hardening type nonl inearities in the dynamic model, application of the standard method of linearization may lead to substantial overestimation of extreme respo nses. It is shown by example studies that the proposed methods may off er significant improvement in the ability to predict extreme responses .