The analysis of columns for the design of pultruded frames: isolated centrally loaded columns

摘要

Linear elastic bifurcation loads are presented for two pultruded I-profiles in order to investigate the ultimate buckling behaviour of centrally loaded columns. The method of analysis is the Finite Element (FE) method. As the height of a column is reduced from a maximum of 6.3m, specific attention is given to the transition height at which the instability mode of failure changes from global Euler to local flange. It is found using FE and test results that this transition height can be within thepractical height range of 3 to 6m, such that ultimate resistance of a column in a frame structure can be governed by local buckling FE critical buckling load results are compared with data obtained in laboratory testing programmes. It is shown that,despite the shortcomings of the FE modelling, the numerical predictions provide new information in our quest to establish reliable and relevant design approaches for both local and Euler buckling.