Structural Performance of Semi-Rigid Connection Steel Frames

Abstract

In most engineering designs, steel connections are usually considered as fully rigid connections or perfectly pinned connections, for simplicity of design work. In reality, this assumption is incorrect. The behaviour of the beam-column connection is in between of rigid connection and perfectly pinned connection. This type of connection is termed semi-rigid connection. This article represents a numerical analysis using finite element method of structural steel frames to investigate the effect of semi-rigid beam-column connection on the behaviour of the frame. ANSYS software was used for the finite element modelling of the frames. The beam-column connection was modelled as rotational spring with specified rotational stiffness using COMBIN14 element. The study includes investigation the effect of semi-rigid on different study cases such as: support types and number of stories. The obtained results reveal that changing the beam-column connection from rigid case to semi-rigid case with different rotational stiffness can increase the vertical and horizontal displacement of the frame with a percentage depends on the rotational stiffness of the beam-column connection. Changing the support type of the frame from fixed to pinned support or increasing the number of stories with semi-rigid connection can decrease the strength capacity of the frame. This indicates the importance of including the semi-rigid connection in the design and analysis of steel frames to obtain more realistic results.