No abstract

Anchor dragging is a major threat to the structural integrity of submarine pipelines. A mathematical model in which the mechanical model of chain and the bearing model of anchor were coupled together. Based on the associated flow rule, an incremental procedure was proposed to solve the spatial state of anchor until it reaches the ultimate embedding depth. With an indirect measurement method for the anchor trajectory, a model test system was established. The mathematical model was validated against some model tests, and the effects of two parameters were studied. It was found that both the ultimate embedding depth of a dragging anchor and the distance it takes to reach the ultimate depth increase with the shank-fluke pivot angle, but decrease as the undrained shear strength of clay increases. The proposed model is supposed to be useful for the embedding depth calculation and guiding the design of the pipeline burial depth.

No abstract

Real-time route planning is always a difficulty in maritime traffic. Route planning must take into account the complex meteorological environment. Route planning based on meteorological environment real-time update is the basis of route feasibility. Based on potential field theory, this paper proposes a TPS - Genetic algorithm for real-time route planning of sailing ships. On the basis of genetic algorithm, combined with the characteristics of route planning, the turning point sorting operation is added to improve the calculation efficiency, and further improve the real-time performance of route planning. Simulation experiments are established and compared with A* algorithm. The experimental results show that the potential field theory can accurately express the dynamic changes of Marine meteorology, and the path planned by TPS - Genetic algorithm is more suitable for real-time navigation environment. TPS - Genetic algorithm can be applied to ship navigation system, which can further adjust the potential energy base and plan routes according to the needs of shipping companies.