Compressive testing and modelling of additively manufactured stainless steel equal angle sections with stiffening wave patterns

• Experimental tests on 3D printed stainless steel equal angle section stub columns and tensile coupons have been carried out. • Numerical modelling validation and subsequent parametric study has been performed. • ‘Higher-order’ wave patterns can increase plate buckling resistances. • Optimum wave patterns have been identified. • Provisional design equations have been proposed for the optimised shapes. Traditional structural steel manufacturing routes typically produce prismatic members comprising of flat plate elements. Under compressive actions, the capacity of these sections is often dominated by plate instability of the lowest buckling mode. The current study involves compressive testing of 6 different configurations of non-prismatic stub columns, comprising of pre-defined surface waves tested at 3 different slendernesses and 3 amplitudes including control prismatic sections. Absolute and normalised load-displacement curves are generated to compare against the control sections and assess the potential increase in strength and stiffness, and the samples’ weights are measured to evaluate the relationship between material use and strength when using this method of strengthening. Tensile coupon tests are also carried out on coupons printed from the same material to define material parameters, and an extensive parametric study is undertaken with numerical modelling software. The best case evaluated in this study indicated a strength gain of 89.9 % over a control section with an equal volume of used material. Eurocode-compatible buckling characterisation curves are then provided for two of the best performing sections. This study highlights the possibilities of this technology, paving the way towards unprecedented efficiency in future steel construction.