ABSTRACT
A composite column is any concrete column reinforced with steel other than reinforcing bars, and can be regarded as a natural development of the original reinforced concrete column. Since rigid or semi-rigid framing is a characteristic of most systems that contain structural concrete, this chapter treats composite columns as if each were in fact a beam-column. Methods for evaluating cross-section thrust and flexural strength are described. Biaxially eccentric thrust is discussed. Shear strength estimates are suggested, and techniques for the rational analysis of slenderness effects are described. Example calculations for strength and for slenderness are included both for an encased steel shape and for a concrete filled steel tube. A brief discussion of connections and auxiliary reinforcement concludes the chapter.
