Scientific Steps Group

The Effect of Using Different Cross-Sectional Shapes of Steel on the Flexural Performance of Composite Reinforced Concrete Beams

September 2, 2023

Various types of structures can be constructed using reinforced concrete, including slabs, walls, beams, columns, foundations, frames, and more. The incorporation of structural steel and reinforcements in concrete enhances the strength and durability of structural elements while compensating for the tensile weaknesses in the concrete material. This study aimed to investigate the behavior of reinforced concrete beams utilizing structural steel of different shapes. Four types of concrete beams were prepared: a standard beam with normal reinforcement, and three composite beams, each featuring structural steel with different sectional shapes – T-section, I-section, and channel section. The consistent parameters included the cross-sectional area of the specimens, each measuring 100x150x450 mm, a steel reinforcement percentage of 2% of the total volume, and the compressive strength of the concrete. The conducted tests involved applying a concentrated load at the mid-span of each beam to examine the specimens’ behavior in terms of strength, flexural load capacity, deflection, crack patterns, and failure mode. The results of this study reveal that, given the same steel ratio, the load capacity of beams reinforced with structural steel of a channel shape has surpassed that of the other beams. Additionally, specimens with structural steel plates exhibited higher maximum deflections before failure compared to the beams with conventional reinforcement.

An Experimental and Numerical Evaluation of the Structural Performance of Concrete Beams Containing Bamboo Shear Reinforcement

June 19, 2023

Alternatives to steel reinforcement in concrete are being actively investigated for environmental, economic, and durability concerns. Several studies suggest that bamboo is a potential substitute for steel reinforcement. In this study, the shear behavior of five reinforced concrete beams incorporating bamboo strips as shear reinforcement at different spaces and configurations were assessed. Structural concrete having a compressive strength of 25 MPa was used for this purpose. The experimental program involved applying four point bending test to the beams to determine their load deflection curves, crack pattern, and strain distribution. In addition, a numerical analysis was conducted for validation and prediction purposes. It was observed that including bamboo strips as shear reinforcement influenced a more brittle behavior with marginal differences when changing their spacing. On the contrary, the spacing was decisive for the load carrying capacity, as smaller spacing caused higher capacity. Strain distribution results followed a similar pattern to that of the deflection. All the curves exhibited a brittle shear failure evidenced by the crack propagation process. Further, the numerical study performed produced accurate results in comparison with the results obtained experimentally, in terms of both the load deflection curves and the crack pattern.