Steel angles are an important class of structural members. They are extensively used in several types of structures for a variety of purposes. They are difficult to analyze and have been studied less extensively than other shapes. In the present work, many research needs have been identified and sol!le of them regarding steel angle behaviour under compressive loading have been addressed in detail.

Twenty-six tests for flexural buckling of steel angles were conducted with five different lengths and six different sizes. Residual stresses in fifteen hot-rolled angle sizes were measured Initial out-of-straightness was estimated A column curve for steel angles was obtained It was found to be close to SSRC column curve no. 1.

Thirty-four specnnens with five lengths and eight sizes were tested for torsional-flexural buckling. Existing design procedures were shown as conservative. A theoretical investigation was also performed It was recommended that torsional-flexural buckling check and plate buckling check need not be carried out simultaneously even for unequal leg angles.

Fifty-five stitch bolted double angles buckling in the plane of connectors were tested with five sizes and three lengths. The specimens included both pretensioned and snug tight bolted interconnectors. The results were examined in light of current design standards. It was recommended that the effective slenderness ratio of the built-up member about the axis of symmetry be increased from that presently adopted. It was also recommended that the criterion of providing more than one bolt per interconnector, if the leg width was equal to or greater than 125 mm, need not be adhered to.

Single angles under eccentric load were examined using past experimental data. The applicability of beam-column interaction equation for angles under compression and biaxial bending was studied It was shown to be conservative in the prese~t form. Empirical improvements were suggested.

Cold-formed steel angles in concentric compression were examined using past experimental data. A maximum strength analysis was performed and a design procedure was proposed.

A design procedure for schifllerized and cold-formed 600 steel angles was presented It was recommended that SSRC curve 2 be used to avoid checking for torsional-flexural buckling