Determination of design plastic strain limit for notched structural steel tensile specimens

Abstract

Steel structures play a central role in construction due to their high strength, ductility, and adaptability in modifying their longitudinal shape or cross-section. However, each modification significantly impacts both the load-bearing capacity and the local distribution of stresses and strains, which are critical factors to be carefully considered during the design process. This study presents the results of numerical and experimental analyses on notched tensile specimens made of S235 steel. Experimental results were used to validate numerical models. Real material properties were obtained from coupon test results, and material models were subsequently developed. A total of 63 numerical simulations were conducted with systematically varied numerical parameters. Corresponding equivalent plastic strains were measured at the analytical design tension resistance and evaluated through reliability analysis in accordance with EN 1990. The equivalent plastic strain limit was determined to be 5.38 %, calculated using the First-Order Reliability Method.