The problem of stress concentration at the corner of composite bars

openaccess, Vol. 646 (06) 2026 / czwartek, 25 czerwca, 2026

Problem koncentracji naprężeń w narożu prętów kompozytowych

(Open Access)

DOI: 10.15199/33.2026.06.02

citation/cytuj: Szczech D. The problem of stress concentration at the corner of composite bars. Materiały Budowlane. 2026. Volume 646. Issue 06. Pages 10-16. DOI: 10.15199/33.2026.06.02

The article addresses the issue of stress concentration at the corner of composite reinforcement. Due to the weakening effect caused by the bending of the bar at the corner, there is a significant reduction in the shear strength of the reinforcement. The shear capacity of bent FRP bars is analysed in the context of design standards, and in comparison with traditional steel reinforcement.

W artykule przedstawiono problem koncentracji naprężeń w narożu zbrojenia kompozytowego. Ze względu na osłabienie zagięcia pręta w narożu następuje znaczna redukcja nośności zbrojenia na ścinanie. Przeanalizowano nośność pręta zagiętego FRP w świetle norm projektowych, a także w porównaniu z tradycyjnym zbrojeniem stalowym.
stress concentration; FRP; stirrups, bent strength.

koncentracja naprężeń; FRP; strzemiona, nośność pręta zagiętego.
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dr inż. Damian Szczech, Politechnika Łódzka, Wydział Budownictwa, Architektury i Inżynierii Środowiska
ORCID: 0000-0002-8357-2877

dr inż. Damian Szczech, Politechnika Łódzka, Wydział Budownictwa, Architektury i Inżynierii Środowiska
ORCID: 0000-0002-8357-2877

Correspondence address: damian.szczech@p.lodz.pl

Full paper:

DOI: 10.15199/33.2026.06.02

Article in PDF file

Received: 02.03.2026 / Artykuł wpłynął do redakcji: 02.03.2026 r.
Revised: 09.04.2026 / Otrzymano poprawiony po recenzjach: 09.04.2026 r.
Published: 24.06.2026 / Opublikowano: 24.06.2026 r.