Stiffness of the component ‘lateral faces of RHS’ at high temperature

The study of semi-rigid joints is one of the main new subjects that have been included in the design codes. In this field, the component method can be considered the most important theoretical approach for the evaluation of the properties of joints. The extension of this method to new fields of application is the aimed objective of this paper and the selected new subjects for this purpose are the consideration of rectangular hollow sections (RHS) and high temperature conditions. In this way, the component characterization is one of the main steps of the component method, and the Eurocode approach requires the calculation of both resistance and stiffness of each one of the component parts in which the whole joint can be divided. In this paper, the stiffness of the component ‘lateral faces of RHS under compression’ was selected to be studied at ambient and high temperature through experimental and numerical research. Finally, these tests were used to check the validity of a new analytical equation for the stiffness of the component ‘lateral faces of RHS under compression’.

Research highlights
► The component method needs to be extended to joints with hollow sections.
► We characterized the lateral faces of RHS under compression at high temperature.
► We proposed analytical equations for the stiffness of the component.
► Experimental tests and FEM showed good agreement with the proposed formula.
► Coefficients for material properties of RHS at high temperatures are suitable.