Análise Numérica dos Efeitos da Corrosão Ascendente e Descendente em Pilares Metálicos de Pórticos de Galpões

Objective - To numerically evaluate the impact of atmospheric corrosion on the mechanical behavior of steel columns in portal frames, considering different heights and directions of deterioration propagation. The study aims to understand how thickness loss influences the stiffness and stability of the structure, supporting design and preventive maintenance decisions. Methodology - The research was carried out through numerical modeling using the Abaqus® software, based on the theoretical model proposed by Vogel (1985). Simulations were performed with B21 beam elements, using a 200 mm mesh size. Corrosion scenarios with progressive thickness reductions were considered over exposure periods of 7, 15, 25, and 50 years, according to the guidelines of ABNT NBR ISO 9223 (2024). Originality/Relevance - The work proposes an approach that correlates the height and direction of corrosion with the loss of structural performance, highlighting critical regions and typical deterioration patterns in steel columns. Results - The results show that ascending corrosion exhibits gradual effects, becoming significant only when it reaches approximately 1.0 m in height, whereas descending corrosion causes noticeable deterioration with extensions as small as 0.4 m. A reduction in stiffness and an earlier onset of structural instability were observed, even with small displacement variations. Theoretical/Methodological Contributions - The study enhances the understanding of localized corrosion effects in structural steel members, presenting a replicable finite element–based simulation method. Social and Environmental Contributions - The research reinforces the importance of durability and sustainability in steel structures, promoting the rational use of resources through preventive maintenance strategies and extension of service life. The practical application of the results may reduce rehabilitation costs, minimize material waste, and contribute to more resilient and environmentally responsible buildings.