考虑弯曲刚度的高压海缆敷设受力分析

TENSION ANALYSIS OF HIGH VOLTAGE SUBMARINE CABLE LAYING CONSIDERING BENDING STIFFNESS

对敷设过程中的海缆进行动力学分析,得出考虑弯曲刚度的动力学微分方程,借助Orcaflex软件分析弯曲刚度、船舶运动、入水角和海床刚度对海缆运动、张力和曲率的影响。通过研究发现:随着弯曲刚度的增大,海缆的1阶频率逐渐增大,最大有效张力和曲率逐渐减小;海缆最大有效张力发生在海缆上端张紧器处,最大曲率发生在海缆离开拖缆架处;海缆敷设时船舶运动影响大于波浪的影响,船舶垂荡运动对海缆的有效张力影响较大,对曲率影响较小;随着海缆入水角的增大,海缆的有效张力减小,曲率增大;随着海床刚度的增大,海缆在触地段处有效张力逐渐减小。

The kinematic differential equation considering the bending stiffness is obtained by dynamic analysis on the submarine cable laying. The effects of bending stiffness,ship motion,water entry angle and seabed stiffness on cable motion, tension and curvature are analyzed using Orcaflex software. The results show that the first order frequency of submarine cable increases with the bending stiffness increasing,but the maximum effective tension and curvature decreases. The maximum effective tension of the submarine cable occurs at the cable tensioner and the maximum curvature occurs when the submarine cable leaves the cable support. The impact of ship movement is greater than that of waves during the cable laying and the heave motion has a great influence on the effective tension but little effect on the curvature. With the increase of the water entry angle,the effective tension of the cable decreases, but the curvature increases. The effective tension of the submarine cable in the touchdown zone is gradually reduced when the seabed stiffness increases.