The generalised slenderness-based resistance method for the design of CHS and EHS

Selected, extended paper from the SDSS 2019 special session ECCS/TC8 - Structural Stability
This paper presents the development and assessment of an innovative cross-section design method for structural steel circular and elliptical hollow sections (CHS and EHS) - the generalised slenderness-based resistance method (GSRM). A numerical simulation programme was first conducted to expand the data pool for CHS and EHS. Finite element (FE) models were established, validated against existing test data and then utilised for parametric studies, where a total of over 3 700 cross-section resistance data were numerically generated. The development of the GSRM for CHS and EHS is then presented. Key design parameters, including the reference resistances and the generalised local slenderness, are initially defined. The general design procedure is subsequently introduced. Two design alternatives for CHS and EHS - a strength-based approach, and a deformation-based approach based on the continuous strength method (CSM), are developed and presented. Finally, the proposed GSRM is assessed using the previously collected test results and freshly generated FE data, where excellent accuracy and consistency in the resistance predictions are clearly revealed for all loading scenarios. Subsequent reliability analyses demonstrate that the current partial safety factor used in EN 1993-1-1 can be applied to the GSRM, achieving an appropriate level of reliability.