Time History Investigation of the Nonlinear Dynamic Behavior of Post-Tensioned Beams

Abstract

The increasing complexity of modern infrastructure necessitates advanced analytical techniques to evaluate structural response under dynamic loads. This study focuses on the non-linear dynamic analysis (NLDA) of post-tensioned concrete beams using time history analysis (THA) to assess their seismic performance. Post-tensioned beams, widely used for their enhanced strength and crack control, employ high-strength steel tendons that are tensioned before loading, improving resistance to tensile stresses. A finite element model is developed using commercial software to simulate the complex interactions between concrete and prestressing tendons. Advanced material models, incorporating smeared crack theories and plasticity approaches, accurately represent the non-linear behavior of concrete under seismic loading. The study employs multiple seismic time history records to analyze key performance indicators such as maximum deflection, energy absorption, and damage states. Results indicate that post-tensioning effectively mitigates seismic damage, enhancing overall structural stability. Additionally, tendon configuration and prestressing levels significantly influence dynamic response, highlighting the need for optimized design strategies. This research provides valuable insights into the seismic resilience of post-tensioned beams, offering engineers essential guidelines for designing more durable and earthquake-resistant structures. The findings emphasize the importance of numerical methods in assessing complex structural systems under dynamic loads.