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This work reports the latest results of an ongoing investigation on the Direct Strength Method (DSM) design of hot-rolled steel equal-leg angle columns with fixed and pinned (cylindrical or spherical hinges) supports and short-to-intermediate lengths, i.e., buckling in flexural-torsional modes. It extends the scope of similar studies carried out by the authors for cold-formed (higher leg width-to-thickness ratios) steel angles with the same characteristics. After reviewing (i) the most relevant findings unveiled in the studies concerning hotrolled steel angles, including the role played by residual stresses in eroding their ultimate strength, and (ii) the available experimental and numerical failure load data, comprising fixed-ended and pin-ended columns with several geometries (cross-section dimensions and length) and reported by various researchers, the paper briefly addresses the mechanical reasoning behind an efficient DSM-based design approach proposed by the authors in the context of cold-formed steel (slender legs) short-to-intermediate angle columns. Then, the available failure load data is used to assess the quality of their estimates provided by this DSM design approach, including the determination of the corresponding Load and Resistance Factor Design (LRFD) resistance factors. It is shown that the proposed design approach can be also successfully applied to predict hot-rolled steel angle column failure loads, leading to LRFD resistance factors above the value currently prescribed, for compression member design, by the North American Specification (φc=0.85).

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A simple bend-draw experimental device is employed to analyze the behavior of narrow strips submitted to a nearly cyclic bending deformation mode followed by a steady state drawing. In this bending-drawing experiment, the strip is firstly bent over a central bead and two lateral beads by applying a controlled holding load and then is pulled out of device throughout the bead radii by a drawing load. The apparatus is mounted in a standard tensile test machine where the holding and drawing loads are recorded with an acquisition data system. The specimen is a rectangular strip cut with 320 mm long and 7 mm wide. The longitudinal (l) and width (w) strip plastic strains are determined from two hardness marks 120 mm spaced whereas the corresponding thickness (t) strain is obtained by volume conservation. Previous experiments showed a correlation between the plastic strain (ε w /ε t ) BD resulting from the bending-drawing and the Lankford R-values obtained from the uniaxial tensile test. However, previous 3D numerical simulations based upon Hill's quadratic and Ferron's yield criteria revealed a better correlation between the (ε w /ε t ) BD and the stress ratio σ PS /σ (α) , where σ PS stands for the plane-strain tension yield stress and σ (α) for the uniaxial yield stress in uniaxial tension along the drawing direction making an angle α with the rolling direction [1] . In the present work, the behavior of an IF steel sheet is firstly evaluated by means of uniaxial tensile and drawing-bending experiments conducted at every 15 degrees with respect to the rolling direction. Afterwards, the bending-drawing experiment is investigated with the commercial finite element (FE) code ABAQUS/Standard in an attempt to assess the influence of cyclic loadings upon the bendingdrawing strain-ratios.

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