Seismic behavior of steel members will be strongly influenced by the difference of material properties. To investigate the effects of material property and the shape of the H-section on the rotation capacity of beam-to-column connections, a detailed finite element analysis are used in this study. In case of considering a ductile crack at the beam-to-column connections, it is important to take into account both width thickness ratio and the ratio of plastic section modulus of web on H-beam (Zwp/Zp). The regions of width thickness ratios whose rotation capacity of beam-to-column connections is not defined by the strength degradation but by the initiation of ductile crack are indicated in this paper.
