Flexural behavior of reinforced concrete arch ribs.

This article focuses on the seismic flexural behavior of reinforced concrete (RC) arch ribs in arch bridges, emphasizing the effects of high axial loads and hollow section configurations. Through experimental tests on scaled RC arch rib specimens with single-cell and double-cell boxed sections under varying axial load ratios, the study found that increasing axial load enhances lateral load capacity but significantly reduces displacement ductility and energy dissipation. The double-cell boxed section exhibited about 27% higher lateral load capacity but 13% lower ductility compared to the single-cell section, while energy dissipation capacities were similar when reinforcement ratios were comparable. Additionally, stiffness degradation was consistent across specimens, and shear deformation was negligible due to the high transverse reinforcement ratio. These findings contribute to understanding the seismic performance of RC arch ribs and inform design considerations for earthquake-resistant arch bridges.