Seafloor Interaction with Steel Catenary Risers

摘要

This paper describes the key features of a seafloor-riser interaction model. The soil is represented in terms of non-linear load-deflection (P-y) relationships, which are also able to account for soil stiffness degradation due to cyclic loading. The analytical framework considers the riser-seafloor interaction problem in terms of a pipe resting on a bed of springs, and requires the iterative solution of a fourth-order ordinary differential equation. A series of simulations is used to illustrate the capabilities of the model. Thanks to the non-linear soil springs with stiffness degradation it is possible to simulate the trench formation process and estimate moments in a riser.