Numerical study of fixed ended lean duplex stainless steel (LDSS) flat oval hollow stub column under pure axial compression

• FE study of LDSS flat oval hollow stub columns is presented.
• Variations in column strength with cross-sectional parameters were studied.
• Maximum strength was seen to be given by flat oval with semicircular end portions.
• The FE results were compared with those predicted by codal specifications.

This paper investigates the effect of cross-section thickness, flat length and curvature of end parts, on the load capacity of fixed ended LDSS (Lean Duplex Stainless Steel) flat oval stub columns, using the commercial finite element software, Abaqus. Based on the FE analyses, it has been found that sections with semicircular elements provided the maximum load capacity, and for flatters, the rate of decrement in load capacity is seen to be small. The effect of flat length on the load capacity, for thinner sections, is found to be relatively insignificant, however for thicker sections, an increase in load capacity is observed, with the slope of increment getting relatively higher as the thickness increases. Strength gain per unit increase in area by 1) increasing thickness, increases with increasing curvature radius and decreases with increasing flat length; 2) increasing flat length, increases with increasing thickness; while the decrease in strength per unit decrease in area by increasing curvature radius decreases with increasing thickness. The FE results have been compared with ASCE 8-02, AS/NZS 4673, EN 1993-1-4, DSM, CSM predictions, and it has been found that ASDM, DSM and CSM are applicable for the design of flat oval LDSS columns.