Finite Element Analysis On The Mechanical Behaviors For Castellated Steel Columns

Castellated members, characterized by light weight, rational section form, large flexural stiffness , high load-carrying capacity, handsome appearance and prominent economic efficiency, and so on, have been widely used in the world. However, analysis and researches of columns in castellated members are not development enough currently. The prevalent use of castellated members has been seriously restricted. So it is necessary to do more researches on mechanical behavior for castellated columns.Finite-element analysis by ANSYS, was used in this paper for the study of mechanical behavior and overall stability for compressive members and compression-bending columns.Finite element models are established in this paper. These models include circular hole and hexagonal hole castellated columns with expansion ratio being 1.4 or 1.5, solid-web steel members without expansion or with the same outline as castellated columns. And then, buckling analysis for the models under axial compression or axial load and flexure is carried out. So the curves of bearing capacity-slenderness ratio for compressive members and relation curves of compression-bending columns are obtained.Through comparative analysis, several conclusions can summarized as follows: when the length of members reaches a certain value, bearing capacity of castellated columns is higher than the original, and its amplitude is increasing by the length. Bearing capacity is seriously close between castellated columns about circular hole and hexagonal hole with the same expansion ratio, but the latter is slightly higher. Bearing capacity of castellated columns with expansion ratio being 1.5 is higher than that with expansion ratio being 1.4 as the length of members reaches a certain value. Compression-bending castellated columns can be used in the short columns of large eccentric and don't suffer the restrictions that axial compressive castellated members are only used in the middle-distance columns. So they have more advantages than axial compressive members.Bearing capacity of castellated columns about strong-axis is researched in this paper and other problems remain to study further.