LATERAL-DISTORTIONAL BUCKLING OF CONTINUOUSLY RESTRAINED COLUMNS

A rational model for predicting the elastic buckling load of thin-wall ed I-section columns, restrained fully against translation and elastic ally against twist at one flange, is presented. The energy method used results in a third-order eigenproblem. The numerical method Is illust rated by considering the elastic buckling of doubly-symmetric and mono symmetric columns with various degrees of elastic twist restraint. It is shown that the buckling mode is of a lateral-distortional type. The accuracy of the U-frame buckling model used in through girders for pr edicting the lateral-distortional buckling load is assessed in the stu dy. (C) 1997 Elsevier Science Ltd.