Analysis on J lay of SCR based on catenary and large deflection beam theory

• We build a model that combines catenary theory and large deflection beam theory.
• Catenary theory for low bending area, large deflection beam theory for high bending area.
• Singular perturbation technique to solve large deflection beam theory equations.
• Parameters sensitivity of top tension, wet weight, and stiffness are calculated.

This paper mainly focuses on J lay of Steel Catenary Riser, and proposes a new model using Sectional Mechanics Model, by iterating and composing catenary method and large deflection method. First the initial deformation and reaction force are evaluated by simple catenary model. For the pipe section with large deformation, asymptotic expansion in singular perturbation techniques pursues the solutions of second-order nonlinear governing equation. Comparison between these three methods shows that the new model displays very close results with high-accuracy large deflection model. This new model is also performed to evaluate the sensitivity of top tension, wet weight, and stiffness on the riser.