Experimental study on the static performance of precast concrete simply supported beams with large‐diameter, high‐strength steel bars

Abstract In the present study, a novel design for a simply supported beam is introduced, which incorporates large‐diameter, high‐strength steel bars within a precast reinforced concrete structure. These beams are connected using a full grouting sleeve. This design aims to address the challenges associated with the use of a large quantity of small‐diameter, small spacing steel bars in precast components, which often result in issues such as difficult vibration control, intricate reinforcement, and unpredictable structural quality. To evaluate the flexural performance of the proposed design, an experimental investigation was conducted. The variables under consideration were the diameter of the tensile reinforcement and the presence or absence of additional waist reinforcement. A total of six specimens were subjected to monotonic static loading tests. Key performance indicators such as deflection deformation, crack width, and bearing capacity were observed. A finite element model is established with ABAQUS software for comparative verification, and the material constitutive relationship suitable for the static performance simulation of such components is determined. The findings indicate that the simply supported beam, when constructed with large‐diameter steel bars, demonstrates favorable bending performance. The load–deflection curve exhibits a distinct turning point, and the structure reveals good ductile failure characteristics. Moreover, as the diameter of the steel bar increases, there is a corresponding increase in the ultimate bearing capacity, but with reduced ductility. The finite element model, which utilized plastic damage and double‐broken‐line material constitutive models for steel bars, yielded calculations that closely aligned with the experimental results.