Sensitivity analysis of the stability problems of thin-walled structures

Analysing the system behaviour in relation to the input quantities it is often necessary to find out what quantities have the greatest effect on the studied output. The article shows the essential methods of applied sensitivity analysis. The objective of the paper is to analyse the influence of initial imperfections on the resistance of a member under axial compression. The analysis uses the Latin Hypercube Sampling simulation method (LHS) [Novák D, Teplý B, Shiraishi N. Sensitivity analysis of structures. In: Proc. of the fifth int. conference on civil and structural engineering computing. 1993. p. 201-07; Novák D, Lawanwisut W, Bucher C. Simulation of random fields based on orthogonal transformation of covariance matrix and Latin hypercube sampling. In: Proc. of int. conference on Monte Carlo simulation. 2000. p. 129-36] together with advanced models based on the nonlinear beam finite element method. The histograms of initial imperfections obtained by measurement [Melcher J, Kala Z, Holický M, Fajkus M, Rozlívka L. Design characteristics of structural steels based on statistical analysis of metallurgical products. Journal of Constructional Steel Research 2004;60:795-808] were considered.