Evaluation of the moment-rotation curve of I beam-to-CFT column connection with endplate,using mechanical modeling

Through this study, a method is presented to estimate moment-rotation (M-) curve of I beam-to-the concrete filled tube (CFT) connections. This method is based on the components method in which components are analyzed and modeled as different mechanical models. These components are considered as springs with specific mechanical properties of stiffness, strength, and rigid bars. Their force-displacement relationship is assumed bi-linear and 3-linear. The connection behavior is assumed through assembling the stiffness of different components. In this study, connection of I beam-to-CFT column with bolted endplate connection under monotonic loading, which has been tested in the laboratory, is evaluated. It must be mentioned that those bolts which penetrated into the column depth have been used in order to create continuity between flanges of the column. The suggested method has been compared with the experimental test and the advanced finite element model in terms of stiffness, strength, and rotational capacity; moreover, its operation was satisfactory.