Global analysis of buildings under fire situation: influence of beam-column connection and number of stories

Abstract Steel-concrete composite connections are crucial for transferring forces between steel and concrete structural elements. Existing literature suggests that most research on composite connections focuses on their isolated behavior. There is a notable lack of research addressing their global behavior, which refers to how these connections interact with the entire structure and its constraints. This study aims to evaluate the impact of the stiffness of steel-concrete composite connections, the location of the fire and the number of stories in buildings subjected to fire conditions. To investigate these factors, eight building models were created using Abaqus® software and subjected to vertical loads. The study found that the 10-story models demonstrated a greater capacity for force redistribution during fires compared to the 3-story models. This was attributed to their stiffer column sections and the presence of a larger number of beams, which facilitated a more efficient load path mechanism, as explained by the Vierendeel effect. Furthermore, the fire resistance time of the buildings was superior to that of isolated connection models, underscoring the importance of considering the overall behavior of structures and the interactions between elements in fire design.