Automated parametric analysis of stress concentration factors using MATLAB and ABAQUS

Stress concentration at geometric discontinuities significantly influences the structural integrity and fatigue life of mechanical components. Stepped circular bars with shoulder fillets are commonly used in engineering systems where load transfer occurs between sections of different diameters, making accurate prediction of stress concentration essential. This study presents an automated MATLAB–ABAQUS framework for high-throughput parametric evaluation of stress concentration factors in stepped circular bars subjected to axial loading. MATLAB was used to generate design-of-experiments parameters and automatically create Python scripts for ABAQUS to perform finite element simulations and extract stress results. A 24 full factorial design of experiments was conducted to investigate the effects of section length, smaller diameter, fillet radius, and larger diameter on the stress concentration factor. Statistical analysis using ANOVA showed that the smaller diameter and fillet radius are the most influential parameters. A regression-based predictive model and a machine learning surrogate model were developed to estimate stress concentration factors directly from geometric parameters, achieving a coefficient of determination R 2 of approximately 0.91. Validation with classical Peterson stress concentration charts showed agreement within 5–8%, confirming the accuracy of the numerical modelling approach and the effectiveness of the proposed automated framework for design exploration.