STUDY ON THEORETICAL ANALYSIS OF MECHANICAL PROPERTIES OF SUBMARINE CABLES BASED ON ENERGY CONSERVATION PRINCIPLE

This paper establishes three theoretical models for the mechanical analysis of submarine cables under axisymmetric loads based on the principle of energy conservation. All three models take into account the initial gap between layers,which is different from the deformation consideration of the helical layer. Model 1 only considers axial deformation,Model 2 incorporates radial deformation on this basis and Model 3 further considers local bending and torsion. Then,the reliability of the theoretical model is verified through a specific example. Finally,the structural mechanical properties of the submarine cable are analyzed. The results show that the radial deformation,local bending and torsion of the helix layer have little influence on the axisymmetric mechanical response of the submarine cable,and it is recommended to use Model 1 for analysis. Under axisymmetric loads,the helical layer is the main bearing component, and the load will cause separation between the layers,with the separation position related to the type and direction of the load. The larger the initial gap,the smaller the stiffness of the submarine cable. The increase of the helix angle will reduce the tensile stiffness of the submarine cable and increase the clockwise/counterclockwise torsional stiffness. The clockwise/counterclockwise torsional sectional performance of the submarine cable is different,with the clockwise torsional stiffness being larger than the counterclockwise torsional stiffness. External water pressure will increase the counterclockwise torsional stiffness,and have no effect on the tensile stiffness and clockwise torsional stiffness. © 2024 Science Press. All rights reserved.