深水系泊缆绳动力响应研究

Research on Dynamic Response of Mooring Lines in Deep Water

考虑波浪、海流、顶部浮体运动与海底接触效应的影响,依据集中质量法建立系泊缆绳柔性力学模型,以一座深水半潜式平台的系泊系统为例,对比研究了各种因素对于缆绳动态张力与水中构型的影响程度,最后采用模型试验方法对数值计算结果进行验证。研究表明:缆绳的动态系泊张力主要由浮体运动所引起,可达总张力的20%左右,海流流速可使得缆绳形态出现大变形,导致缆绳卧底长度发生明显改变,危及平台作业安全,波浪与海底摩擦对于缆绳响应的直接作用较小,设计阶段基本可以忽略不计。

Considering wave, current, the motion of plaOCorm and the touch effects of the seabed, a flexible mechanics model of the mooring line in deep water is established according to lumped mass method. As an example, the dynamic response of a mooring line of a semi-submerged platform is obtained and the influence of some factors on the tension and configuration is compared. Finally, the model experiment is carried out in order to verify the results. It shows that the dynamic tension which makes up to 20% of the whole tension is mainly caused by the motion of the floating plaform, the current will induces large deformation of the mooring line configuration and the lying length of cable changes significantly, which makes the platform in danger. The effect of wave and the friction of the seabed play a small role in the response of the cable and can be ignored at the design stage.