Buckling analysis of frames with imperfections and uncertain parameters

The paper describes a procedure for the reliability analysis of frame structures with respect to the buckling limit state under the assumption that the elastic parameters are uncertain and modeled as random variables. The procedure relies on a Response Surface Method adopting simple ratio of polynomials without cross-terms as performance function. Such a relationship approximates analytically the dependence between the buckling load and the basic variables furnishing a limit state function which is very close to the exact one when a proper experimental design is adopted. In this way a Monte Carlo Simulation applied to the response surface leads to a good approximation with low computational effort. Some numerical examples show the accuracy and effectiveness of the method, for different values of probability failure. Copyright © 2010 by ASME.