Design of Composite Columns-Steel, Concrete, or Composite Approach?

Composite columns are a combination of two traditional structural forms: structural steel and structural concrete. As composite columns were generally developed after steel columns and reinforced concrete columns, their design approach could have been based on either steel or concrete design methods. However, steel column design methods have differed from concrete design methods in a number of fundamental ways. Despite this, either design approach can be used as the basis for developing a design method for composite columns and this can be seen in the different methods currently used in Europe and the USA for composite columns. While the design approaches appear fundamentally different, the end results can be surprisingly similar. By understanding the design philosophies, designers can take full advantage of each approach for the effective use and economy of composite columns.