The seismic behavior of structural steel members are influenced significantly by the difference of material properties. Therefore, it is very important to clarify the correlation between material properties and structural behaviors. In this paper, FEM analyses are conducted to consider the influence of material properties on the rotation capacity of the beam-to-column connections. The equations that can evaluate the rotation capacity quantitatively are proposed. These equations are not only considering local buckling but also fracture at the beam end. Finally, the regions of the width-to-thickness ratio, collapse mode will be defined by fracture, are proposed.
