Numerical modelling and design of hybrid carbon‐stainless steel bolted T‐stubs in tension

Abstract

Building on previous experimental work by the authors on hybrid T‐stubs with carbon steel webs and stainless steel flanges under tension, this study presents the development and validation of an advanced finite element (FE) model capable of accurately predicting the overall behaviour, failure modes, and fracture mechanisms of bolted T‐stubs in tension. Key simulation approaches and the fracture model formulation are detailed. The validated model is then employed to perform parametric studies on hybrid T‐stubs with varying geometric configurations to examine the influence of plate thickness, material grade and bolt spacing on the ultimate capacity, ductility, and overall response. Based on the findings, the applicability of EN 1993‐1‐8 design rules is critically evaluated, and is found to be overly conservative due to the adoption of an assumed elastic‐perfectly plastic material response with the 0.2% proof strength employed as an equivalent yield strength. Design recommendations are proposed to improve the accuracy and efficiency of design predictions.