浮体垂荡激励下深海悬链线立管触地端动力响应及沟槽发展研究

Dynamic response and trench development of deep-sea steel catenary riser touchdown section under floating bodies’ heave excitation

基于Randolph-Quiggin非线性管土作用模型,借助ABAQUS Subroutine功能中的User Defined Element(UEL)拓展模块创建钢悬链线立管触地单元,研究了顶端垂荡激励下立管触地段动力响应特性。通过与模型试验结果比较分析,验证了开发的数值分析模型的合理性,并讨论了其相较传统线性管土作用模型体现出的优势。开展参数敏感性分析,深入探讨了立管顶端垂荡幅值及周期对沟槽形状、立管位移及弯矩响应等的影响效应。

Based on Randolph-Quiggin nonlinear riser-soil interaction model, dynamic response characteristics of a steel catenary riser(SCR) touchdown section under its top floating bodies’ heave excitation were studied. Touchdown elements of the SCR were developed by using the user defined element extension module(UEL) in subroutine function of ABAQUS. The rationality and effectiveness of the developed numerical model were verified and its advantages over those of the traditional linear model were discussed by comparing to model test results. The effects of amplitude and frequency of top heave excitation on seabed trench shape, riser displacement and bending moment response were deeply explored with parametric sensitivity analysis.