Applicability of an Asymptotic Expansion for Elastic Buckling Problems with Mode Interaction

Asymptotic expansions often provide relatively simple formulas for post-buckling and imperfection sensitivity analyses. In a previous work, Byskov and Hutchinson developed and utilized an expansion to determine the increase in imperfection sensitivity caused by interaction between two or more buckling modes. This article contains an attempt to assess the range of validity of that expansion. The estimates of the applicability are made with reference to a simple example.