Peridynamics formulation for beam structures to predict damage in offshore structures

摘要

Progressive damage analysis of structures is still a major challenge. Peridynamics is a non-local theory using the integral equations rather than differential equations which makes it suitable for damage prediction. In this study, a novel bond based peridynamic model is developed for three-dimensional complex beam structures with 6 degrees of freedom based on Timoshenko beam theory. The numerical algorithm for dealing with complex beam structures is provided for the first time in the peridynamic literature. A damage criterion for beam structures with 6 degrees of freedom is also presented. The validity of peridynamic predictions is established by considering various examples. Initially, the proposed peridynamic model is used to predict the structural behavior of straight and curved beams. Next, the proposed peridynamic model is used to investigate a jacket platform. The jacket platform is subjected to both static and dynamic sea load induced by waves, winds, and currents. The peridynamic predictions are verified by comparing with finite element solutions. Peridynamic damage prediction for a pre-notched beam is verified by comparing with the previous literature. After verifying the peridynamic model, the proposed model is used to predict damages for a jacket platform due to sea loads and due to ship jacket platform collisions.