Flexural Behavior of Reinforced Concrete Beams with Varying Carbon Content in Steel
Received: 27 November 2025 | Revised: 20 January 2026 and 9 February 2026 | Accepted: 11 February 2026 | Online: 4 April 2026
Corresponding author: Fakhruddin
Abstract
This study examines the influence of carbon content in reinforcing steel on the flexural behavior of reinforced concrete beams subjected to two-point loading. Three categories of reinforcing steel were investigated: low-carbon (0.302%), medium-carbon (0.318%), and high-carbon (0.411%), with three beam specimens tested for each type. The average ultimate loads (Pu) were 48.78 kN for Low-Carbon Bars (LCB), 57.39 kN for Medium-Carbon Bars (MCB), and 62.28 kN for High-Carbon Bars (HCB). The corresponding average mid-span deflections at ultimate load were 85.14 mm, 51.09 mm, and 47.72 mm, respectively. An increase in carbon content resulted in an approximately 28% increase in ultimate strength from LCB to HCB, accompanied by a 54% reduction in ductility (μ). In terms of structural response, LCB beams exhibited significant plastic deformation and gradual flexural crack development, indicating high energy dissipation capacity. MCB beams demonstrated a balanced combination of strength and ductility. In contrast, HCB beams achieved the highest strength but exhbited limited post-yield deformation and more pronounced crack localization.
Keywords:
carbon content, reinforcing steel, reinforced concrete beam, flexural behavior, ductilityDownloads
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Copyright (c) 2026 A. Adelia Marsella, Rudy Djamaluddin, Fakhruddin
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