基于大挠度曲线梁模型和弹性地基梁理论,研究了钢悬链式立管与海底相互作用的模拟方法。采用大挠度曲线梁模拟钢悬链式立管的悬垂段,采用弹性地基梁模拟海底流线段。钢悬链式立管与海底相互作用模型不仅考虑了弹性支撑反力和摩擦力,还考虑了动态效应的阻尼力和液化土的吸力。分析表明,采用大挠度曲线梁和弹性地基梁模型分析钢悬链式立管,其单元尺寸的影响较小,可采用较大的计算单元,从而缩短计算时间、减少内存。基于该方法的开发程序与商用程序OrcaFlex吻合较好,但对单元长度的敏感性远远小于OrcaFlex。
The simulating method of the interaction between a steel catenary riser (SCR) and seabed is studied based on an extensible curve beam with a large curvature and a beam on an elastic foundation. The sagbend section and the flowline section of steel catenary risers are modeled by an extensible curve beam with a large curvature and a beam on an elastic foundation respectively. Not only the support and the friction of seabed are taken into account, but also the suction and damping force of seabed are included in the model of the interaction between steel catenary riser and seabed. The results show that the effect of the element length of the model on the analytical result is insignificant and a longer element could be used for the model. Thusly, the analysis is not time-consuming and the memory requirement is not so large by using the model. It is shown that the results computed by the model are consistent to that by commercial code OrcaFlex. But the element length of the model is not sensitive as much as that of OrcaFlex.