It is important to estimate the structural safety of column base connection by calculating exact collapse loads. Column bases connection transfer reactions from the structure the foundation. In this paper, a simple mechanical model to predict their plastic resistance is proposed. An efficient linear-programming technique, which is called as Compact Procedure, is applied to column base connection model including multi-spring elements, where a column base is replaced by a set of plastic axial and bending springs. In Compact Procedure, it is not necessary to know the whole interaction surface of resistances at a plastic portion. A simple analytical model of column base connection to calculate its load-carrying capacity considering bi-axial loading effect is presented. In addition, efficiency of the proposed model is examined by comparing it with the past test results.