Flexural Behavior of Reinforced Concrete Beams under Eccentric Load

Zaid Jaafer Mosa; Hussam Ali Mohammed

doi:10.48084/etasr.11144

Authors

Zaid Jaafer Mosa Building and Construction Department, Al-Furat Al-Awsat Technical University, Babylon, Iraq
Hussam Ali Mohammed Building and Construction, Al-Furat Al-Awsat Technical University, Babylon, Iraq

Volume: 15 | Issue: 4 | Pages: 24788-24793 | August 2025 | https://doi.org/10.48084/etasr.11144

Received: 27 March 2025 | Revised: 26 April 2025, 7 May 2025, and 20 May 2025 | Accepted: 24 May 2025 | Online: 2 August 2025

Corresponding author: Zaid Jaafer Mosa

Abstract

Eccentric loading affects the structural behavior of all components in a system. While eccentric loading has been generally addressed, its direct impact on beams has not been thoroughly investigated. This study focuses on how eccentric loading influences the performance of Reinforced Concrete (RC) beams constructed with Normal Concrete (NC, C30) and High-Strength Concrete (HSC, C70). The experimental program included sixteen beams, each measuring 150 mm × 200 mm × 2000 mm and designed with identical reinforcement. The key variables examined were the type of concrete used, the inclusion of steel fibers, and the difference between centric and eccentric loading conditions. All beams were tested using two-point loading applied through a 100 mm diameter circular steel plate. For the centric loading, the plate was positioned at the center of the beam's top surface, while for the eccentric loading, it was shifted toward the edge along the x-axis. The results showed that eccentric loading did not negatively affect the flexural performance of the beams. HSC beams demonstrated an approximate 10% increase in ultimate load capacity compared to NC. Additionally, incorporating steel fibers improved the ultimate strength by 6% in NC and 10% in HSC. While these gains were modest, they played a significant role in enhancing the overall performance of the beams, especially regarding Absorbed Energy (AE).

Keywords:

eccentric load, normal concrete, high-strength concrete, steel fiber

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