Discrete vs Smeared Modelling Strategies for TRM – Strengthened Beams: A Benchmark Study

Abstract:

Textile-Reinforced Mortar (TRM) is increasingly used for strengthening reinforced concrete structures, yet the selection of an appropriate finite element modeling strategy remains ambiguous. While simplified smeared models are often employed for their computational efficiency, their accuracy for complex multi-layer TRM applications is not well-established. This study presents a critical evaluation of three distinct modeling approaches in ATENA3D—discrete fiber modeling with perfect bond, a smeared reinforcement model, and discrete modeling with a bond-slip interface—for simulating the flexural behavior of full-scale RC beams strengthened with TRM. Validated against experimental data, the results reveal a stark divergence in predictive capability. The smeared approach severely underestimated the capacity of beams with four TRM plies by up to 48%, demonstrating its fundamental inadequacy for modeling layered composites. In contrast, both discrete modeling approaches accurately captured the structural response, with deviations below 21% for all multi-ply scenarios. It is concluded that discrete modeling is essential for the reliable simulation of multi-ply TRM systems, whereas smeared models are only acceptable for preliminary single-ply analysis. This work provides crucial guidance for researchers and practitioners, steering the numerical analysis of TRM-strengthened members toward more reliable and defensible modeling practices.

• Periodical: Construction Technologies and Architecture (Volume 23)
• Pages: 67-73
• DOI: https://doi.org/10.4028/p-a0jgGr
• Online since: May 2026
• Authors: Fawwad Masood*, Syed Salman Mobeen
• Keywords: Atena 3D, Finite Element Modelling (FEM), Strengthening, TRM/FRCM Modelling

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