考虑跨肩管土作用的悬跨管道涡激振动特性研究

Study on vortex-induced vibrations(VIV) of free spanning pipeline considering pipe-soil interaction boundary conditions

海底悬跨管道涡激振动是一个复杂的流场-管道结构-跨肩土体耦合问题,其发生机理和振动特性十分复杂,特别是两端跨肩处管土作用对涡激振动的影响有待深入讨论。为此,文章引入了P-y曲线描绘跨肩处管土耦合作用,提出了基于管道位移和速度的新非线性土体弹簧模型,根据能量平衡原理计算土体阻尼,采用尾流振子模型模拟悬跨管段流固耦合作用,建立了考虑流—固—土多场耦合作用的海底悬跨管道涡激振动预报模型,并重点研究了考虑跨肩管土作用时,悬跨管道涡激振动的诸多特性。

Vortex-induced vibrations(VIV)of free spanning pipeline is a complex fluid-structure-soil coupling problem.Especially the effect of pipe-soil interaction in the shoulders on VIV was not investigated deeply.In this paper,the P-y curve was used to model pipe-soil interaction in the shoulders,a new nonlinear soil spring which is based on the displacement and velocity of pipeline was proposed,the soil damping was calculated according to energy balance principle,the wake oscillator model was employed to describe the fluid-structure interaction,the VIV prediction model was built considering fluid-structure-soil coupling,and the characteristics of VIV of free spanning pipeline considering pipe-soil interaction were discussed in details.