Field of application of high strength steel circular tubes for steel and composite columns from an economic point of view

This paper presents the results of a global comparison between high strength steel and normal steel circular tube used to build steel and composite columns submitted to static loading, as regards the economic aspects. The comparison is based on an optimum design taking into account the strength, stability and stiffness conditions of Eurocode 3 and 4. The automatic implementation of the algorithms allows achieving a high amount of case studies, covering the realistic possibilities of building columns. The investigations are realized on simple columns, columns included in braced or un-braced frames and whole frames. The field of application of high strength steel (vs normal steel), regarding the total cost of the member, is provided in a chart clearly indicating where the use of high strength steel becomes economic.

Research highlights
► We compare the economic interest of the high strength steel with the normal steel.
► The steel and the composite columns using circular steel tubes are considered.
► The comparisons are based on the optimal designs.
► The requirements of the current Eurocodes are used in the optimal designs.
► Many possibilities of the columns are examined leading to the general conclusions.