Class 3: Elastic bending moment resistance develops but local buckling prevents the development of plastic resistance. The design resistances of the profiles correspond to cross-section resistances reduced by the partial material factor γ M0 in accordance with EN1993-1-1 §6.

They are calculated by adding the contribution of the external boundary and then subtracting the contribution of the internal void. The plastic section modulus W pl is calculated by adding the contribution of the external boundary and then subtracting the contribution of the internal void.Similar to RHS sections, hot rolled SHSs are made at the mill as one piece, whereas cold formed SHSs are made of a flat sheet rolled at right angles and welded. The aforementioned design resistances do not take into account a) flexural buckling, b) local shell buckling, c) interaction effects of axial force, shear force, bending moment, and d) interaction effects of biaxial bending. Due to symmetry the centroid of the cross-section (center of mass) as well as the shear center are located at the center. Touch Screen Zoom: Increase the size of the calculator on your touch screen by zooming with your fingers.

Text Size: In some browsers, such as Chrome desktop, you can change the text size in your browser settings and the size of the calculator, text and buttons will get larger or smaller proportionately. The basic geometric properties of the cross-section are calculated by using the fundamental relations of mechanics.The design plastic resistance of the cross-section in uniform compression for cross-section class 1, 2, 3 is specified in EN1993-1-1 §6. The geometric quantities include the total area of the cross section A and the second moments of the area I, which is constant for any axis of bending due to symmetry.