Nonlinear finite element modeling of reinforced concrete beams

Document Type : Research Article

Authors

1 Faculty of Civil Engineering, University of Guilan, Guilan, Iran.

2 PhD Student in Civil Engineering, Faculty of Civil Engineering and Environment, Amirkabir University of Technology, Tehran, Iran

3 3. Distinguished Professor, Faculty of Civil Engineering, University of Semnan, Semnan

4 MSc in Civil Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran.

Abstract
Nonlinear behavior of reinforced concrete beams is complex due to the formation of multiple cracks and the interaction of various internal forces. Therefore, accurate prediction of this behavior requires experimental investigations and numerical modeling based on nonlinear finite element analysis. The objective of this study is to present effective and reliable approaches for modeling reinforced concrete beams in the software Vector2, as one of the widely used tools for concrete structural analysis. For this purpose, four rectangular reinforced concrete beams selected from existing experimental studies are simulated using Vector2. The influence of key modeling parameters on the accuracy of numerical results is investigated and their optimal values are identified. The analysis results indicate that the finite element model employed in Vector2 is capable of predicting load–displacement curves and cracking patterns with satisfactory accuracy. Moreover, the proposed approach is able to simulate beam behavior governed by both flexural and shear failure mechanisms.

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  • Receive Date 06 December 2025
  • Revise Date 25 December 2025
  • Accept Date 08 January 2026
  • First Publish Date 07 February 2026
  • Publish Date 22 May 2026