This study presents a refined approach to the analysis and design of rectangular tied reinforced concrete columns subjected to axial thrust and biaxial bending. One of the several techniques for the design of concrete columns currently in use is thoroughly examined, organized into a logical procedure and converted into graphical form to be used as design aids. Due to the character of the resulting charts the scope of this study is limited to the construction and illustration of design charts only so far as to convey the process by which they were formulated. It is intended for the future that a complete set of design charts be constructed for use over a large range of design parameters to serve as functional design aids for the structural engineer.Architectural Engineerin