Linear Buckling Analysis of Compressed Members combining the Generalised Beam Theory and the Finite Element Method

摘要

A finite element procedure to carry out linear buckling analysis of compressedrnmembers has been developed on the basis of the existing generalised beam theoryrn(GBT) and constrained finite strip method (cFSM). The procedure allows designersrnto uncouple the buckling modes of a finite element model and, consequently, torncalculate pure elastic buckling loads. This is achieved by constraining the finiternelement model according to the pure deformational modes that result from therngeneralised beam theory. The procedure was initially developed to uncouple therndistortional mode of buckling. Since good results were obtained, the procedure isrnnow extended to local and global modes. The present investigation shows the firstrncalculations of pure local and global elastic buckling loads of channel cross-sections.rnThe results obtained are rather accurate when compared to the values calculated viarnGBT and cFSM. Consequently, it is verified that linear buckling analyses can bernperformed with the finite element method in a similar way as it is done with thernexisting GBT and cFSM procedures.