Ultimate Strength of Tubular Beam-Column

To provide a basis for the development of interaction diagrams for round tubular beam-columns, a general purpose beam-column program is used to determine ultimate load capacities. A recursive technique is employed in association with moment-thrust-curvature data generated by an iterative solution for partially yielded cross sections. The program permits axial load, external end moments, or transverse loads to be incremented by a variable step procedure that is terminated at failure. It also provides the option of incorporating longitudinal residual stress patterns and nonlinear configuration of stress-strain relationships into the model. A comparison is made between interaction diagrams developed with and without considering residual stresses. Experimental data and analytical results are also compared, and reasonably close agreement between the predicted and measured values of ultimate capacities are observed.