Addressing the challenges of long-term reliance on imported products and the underdeveloped fatigue life evaluation system for flexible riser connectors in deepwater resource development, this study investigates a bonded flexible riser-floating platform system at a water depth of 1 200 m. A design and evaluation methodology for connectors based on multibody coupled dynamics and fatigue damage evolution mechanism is proposed. First, a coupled dynamic model of the platform and pipeline was established using OrcaFlex to extract time-history data for effective tension and bending moment at the pipe-end interface. Then, parametric finite element models of two connector types-hybrid and crimped-were developed, and their stress responses and fatigue damage were accurately simulated on the ANSYS platform. Finally, a fatigue life evaluation system accounting for multiaxial stress states was established by integrating the rainflow counting method with S-N curve theory. The results demonstrate that, compared to the crimped connector, the hybrid connector exhibits a 30% lower maximum stress level and a more uniform stress distribution, indicating superior structural synergy and fatigue resistance.

In the report, the vibration stability of fluid conveying pipe under two-parameter foundations with elastic support boundary conditions was investigated. Based on the Euler-Bernoulli beam theory, the Hamiltonian principle was used to establish the dynamic equations of the pipe. The change of spring stiffness simplified the elastic support boundary conditions at both ends into various boundary conditions. The harmonic differential quadrature (HDQ) method was used to discrete and solve the vibration equations. The effects of the different spring stiffnesses, two parameter foundation parameters, and the fluid mass ratios on the critical velocity, critical frequency, and modal shape of the pipe were analyzed. The results indicated that the elastic foundation could effectively improve the stability of pipeline vibration. Additionally, the spring support and foundation had a significant effect on the vibration modes of the pipe.