Abstract:
Construction industry has been witnessing an increasing use of stainless steel members, especially, when there is a demand for higher strength to weight ratio, good corrosion resistance, low maintenance cost, high ductility, impact resistance, fire resistance, durability, recyclability etc., despite their higher material cost as compared to carbon steel. However, it has now become possible to offer cost-effective stainless steel material, with the introduction of a relatively new class of stainless steel called Lean Duplex Stainless Steel (LDSS / LDX 2101 / EN 1.4162 / UNS 32101). LDSS offers relatively cheaper cost (as compared to austenitic stainless steel), higher strength, acceptable weldability and fracture toughness properties, improved high temperature properties, etc. It may be mentioned that, in a recently amended EN 1993-1-4 (2006; A1:2015), LDSS has been included. Thus, in this thesis, an attempt has been made to systematically investigate the structural behavior of aesthetically pleasing and relatively new LDSS flat oval (a composite section of flat and curve elements) hollow columns under pure compression. Parametric study on the structural behaviour (e.g. deformation modes, load capacity) of fixed ended LDSS flat oval hollow section stub column, is presented, considering variation of lf (flat length), r (curvature radius), t (thickness), keeping w (flat plate spacing) and h (height of column) constant, using the finite element (FE) analyses. Based on the study, an expression has been proposed for calculating the effective thickness of curve elements of slender (w/t ≥ 40) sections, for reliable load capacity predictions when used with ASDM, AS/NZS 4673, and EN 1993-1-4 equations. Applicability of DSM (Direct Strength Method) and CSM (Continuous Strength Method) have also been verified.
