Investigating the behavior of steel moment connections using advanced component method

One of the most widely used analytical methods to investigate the bending behavior of joints is the component method, which is mentioned in Eurocode 3. However, this method has some shortcomings such as a large amount of calculation, its reliability-low and its weaknesses in the post-yield behavior of the moment-rotation curve. In this research, to make the component method more efficient and reliable, this method was developed in the three mentioned aspects in such a way that the calculations of the method became more compact, the post-yield part of the moment-rotation curve was developed beyond the concept of Eurocode 3 and then it was used for fully welded and end plate connection. In the following, the obtained moment-rotation curves were verified by comparing them with the curve extracted using the laboratory method and finite element method in ABAQUS. In the end, parametric investigations within sensitivity analysis framework were carried out on these connections using advanced component method. The findings indicated that the advanced component method (the method developed in this research) compared to the conventional component method in Eurocode 3 can accurately predict the plastic part of the moment-rotation curve of the two connections. So that the difference percentage of the ultimate moment for the six-bolt extended end-plate connections in the comparison of the laboratory model with the outputs of conventional and advanced component method was obtained as 31.56 and -2.46 percent, respectively. compared to the outputs of the finite elements approach using ABAQUS, the difference percentage of initial stiffness and the moment of the connection is -14.75 and 5.55 percent respectively for the fully welded connection has been examined and -2.98 and 20.09 percent for the eight-bolt extended end-plate connections. Furthermore, it became clear that among the geometrical parameters studied for the two connections, the beam depth has the greatest effect on the change of the initial stiffness and the moment of the connection, as in the end plate connection has been examined, reducing the beam depth by 20 percent decreases the initial stiffness and the moment of the connection by 27.53 and 21.54 percent, respectively, while by increasing the beam depth by 20 percent, the initial stiffness and the moment of the connection increases by 28.65 and 21.54 percent, respectively.