Mechanical characteristics and design parameter analysis of spherical hinge structure for swivel bridge

Abstract As the core component of a swivel bridge, the spherical hinge structure exhibits complex mechanical behavior under high pressure, making it challenging to describe accurately through theoretical analysis or on-site monitoring. In this context, this paper systematically examined the mechanical characteristics and key design parameters of a simplified spherical hinge structure using numerical simulations and formula derivation. Additionally, an indoor scaled test was conducted based on a representative spherical hinge structure to further investigate its mechanical properties. The findings indicated that contact pressure along the spherical hinge interface increased radially outward and followed a cubic distribution pattern. The support radius was identified as the most critical factor influencing the maximum stress value within the spherical hinge structure. In the aperture ratio range of 0.042 to 0.083, the upper and lower spherical hinges are unable to achieve coordinated deformation under high pressure, resulting in negative pressure at the edge of the pin hole. Furthermore, for spherical hinge structures with sliders, the presence of the slider introduced additional complexity to the stress state, leading to a coexistence of tension and compression on the surface of the lower spherical hinge. The highest stress occurred between the inner ring slider and the pin hole, an area that requires careful monitoring. The research provides valuable insights for the design of spherical hinges in swivel bridges and can guide the development of spherical hinge structures tailored to different bridge types in the future.