Initial rotational stiffness of end-plate connections based on the theory of plates and shells

Abstract

With current developments in the optimization design of the building structure, and due to the need for the optimization design to carry out multiple iterative calculations, the accuracy and efficiency of these structural calculations are increasingly required. However, the traditional calculation method of the initial rotational stiffness (Rini) of the beam-to-column connection has certain limitations, and the efficiency of the finite element calculation method is poor. To establish an accurate method for predicting the initial rotational stiffness of major- and minor-axis end-plate connections, the theory of plates and shells and the finite difference method (FDM) are used to analyze the connection following the base on component method. In this study, boundary condition equations were established first based on the theory of plates and shells, for components that undergo significant lateral deformation, namely, the end-plate, column flanges, and column web. Then, the FDM was employed to solve these equations to determine the deformation of these components. Considering the deformation compatibility conditions as well as the force equilibrium conditions, the bolt load at the unit moment was calculated. Finally, based on the stiffness of each of connection components and the bolt load, the Rini of an end-plate connection was calculated. A comparison of the Rini values calculated by the proposed method and those obtained from the experiment (EX), finite element analysis (FEA), and Eurocode 3 (EC3) indicated that the proposed method is more accurate.