Behavior of Built-Up Composite Columns

The results are presented of an investigation into the behavior of pin-ended composite columns containing more than one steel component. A series of tests was performed on built-up composite columns containing two steel channels with and without battens and encased in unreinforced concrete. Comparative tests were made on similar unencased columns. An iterative inelastic analysis for composite columns has been developed to predict their behavior right up to collapse. Comparisons between theoretical and experimental behavior were made. The observed results confirm the analytical predictions and lead to the conclusion that the absence of battens does not detract from the load-carrying capacity of built-up composite columns of the type considered.