The main objective of this study was to evaluate methods of designing uniaxially loaded slender reinforced concrete columns in braced frames. An analytical method was used to predict capacities of a broad range of slender concrete columns. The method incorporates the nonlinear behaviour of concrete sections, time dependent effects, and the nonlinear response of slender columns. The accuracy of the current ACI Moment Magnifier Method of accounting for slenderness effects is studied. Large conservative errors inherent in this method are identified and discussed. It is concluded that slender concrete columns in braced frames can be designed more easily and with greater accuracy by an emperical direct moment magnification method. Such a method, involving the use of graphs, is presented for the design of columns with rectangular sections. The accuracy and limitation of this method are discussed and recommendations for further study are made.

Master of Engineering (ME)