Numerical estimation of the initial stiffness and ultimate moment capacity of single-web angle connections

• A simpler and more accurate equation for the initial stiffness is suggested.
• The type of collapse mechanism is established.
• The effective length ratio of the angle is proposed.The ultimate moment capacity modified from Kishi and Chen's equation is proposed.

Single-web angle connections bolted to the beam web and the column flange are studied to investigate the effect of the thickness, length, and material properties of the angles, number of bolts, and gage distances of the fasteners on their moment–rotation behavior. ABAQUS software is used to analyze the nonlinear behavior of a single-web angle connection. Identical geometric and material properties with Lipson's test are utilized to verify the finite element models. A simpler and more accurate equation for the initial stiffness is suggested, and good agreement between the proposed model and Lipson's test data is demonstrated. The type of collapse mechanisms for single-web connection is established. The ultimate moment capacity modified from Kishi and Chen's equation is also proposed, and it agrees well with Lipson's test data.