An experimental and numerical evaluation of the structural performance of bamboo-reinforced concrete beams

The global shift toward sustainable construction calls for eco-friendly alternatives to traditional materials. While steel reinforcement in concrete offers high strength and durability, it has significant environmental and economic drawbacks. Bamboo, a fast-growing and renewable material, is a low-cost, eco-friendly option, but concerns about its structural performance have hindered its widespread use. This study examines the structural performance of concrete beams reinforced with steel (SRC), bamboo (BRC), and hybrid steel-bamboo combinations (HYB-1 and HYB-2). It assesses ultimate failure load, load–deflection curves, failure modes, and crack patterns to explore their viability as sustainable alternatives. Beams measuring 150 × 150 × 750 mm were tested experimentally and simulated using ABAQUS software under three-point bending. SRC beams had the highest ultimate failure load (104.67 kN) and deflection (8.6 mm). BRC beams had the lowest failure load (17.97 kN), a decrease of 82.9% compared to SRC beams. HYB-1 and HYB-2 showed intermediate loads of 87.25 kN and 24.99 kN with a decrease of 16.6% and 76.1% respectively compared to SRC reference samples. Deflection in BRC beams was the least (3.0 mm), while HYB-1 and HYB-2 showed deflections of 7.4 mm and 5.6 mm. The average flexural strength for BRC beams was 82.8% lower than SRC beams, while HYB-1 and HYB-2 showed reductions of 16.9% and 76.1%. The energy absorption capacity of HYB-1 beams was close to SRC beams, with only a 29.1% reduction, while BRC and HYB-2 beams showed a reduction of 92.8% and 87.1% respectively compared to SRC beams. These findings suggest that hybrid configurations, particularly HYB-1, balance structural strength and sustainability Finite element analysis (FEA) closely matched experimental results, with an average difference of 7.44%, validating the accuracy of the modeling.