The Influence of Key Dimensions of the Swivel Hinge on the Mechanical Performance of Bridge Rotary Structure

To assess the influence of the spherical and supporting radius of swivel hinges on the anti-overturning capability of T-structures and the safety of lower turntables, this study focuses on large-tonnage rotary bridges spanning the South-to-North Water Diversion Project along the Jiaozuo to Tanghe Expressway. The research involved theoretical analysis and numerical simulations to evaluate the stability of the rotary structures and the load-bearing capacity of rotary platforms with varying spherical and supporting radii, and we generated 15 numerical models. The results indicate that the critical eccentricity for T-structure anti-overturning increases with larger supporting and spherical radii, with diminishing returns as the supporting radius decreases. The critical eccentricity for spherical hinges is consistently lower than that seen for flat hinges. The lower turntable’s failure characteristics divide it into four zones, as follows: main compressive stress failure at the bottom under the hinge, main tensile stress failure at the top around the hinge, and two other regions less prone to failure. The supporting radius significantly influences compressive and tensile stress failures, while the spherical radius mainly affects the tensile stress area. These results offer insights for the design and construction of large-tonnage rotational bridges.