Assessment of the Global Behavior of Reinforced and Prestressed Concrete Buildings in the Context of Geometric and Material Nonlinear Analysis.

Resumo

This study aims to present a comparative analysis of the global behavior of buildings modeled using reinforced concrete and prestressed concrete, with emphasis on the evaluation of the global instability of the structural frame. The analyses are conducted using three-dimensional models that incorporate both physical and geometric nonlinearities, with the effective stiffness of structural elements extracted from an equivalent spatial frame. These values are compared against the stiffness coefficients prescribed by NBR 6118 (ABNT, 2023), enabling a critical assessment of the representativeness of these parameters in relation to the actual structural behavior. The study also addresses the increase in global stiffness provided by the introduction of prestressing and its impact on structural stability, in light of international standards that account for prestressing effects in ultimate limit state analyses. The results aim to contribute to the advancement of structural modeling and the prediction of global instability in buildings, offering technical insights for a more accurate and safe design approach.