连续跨海底悬空管道动力响应非线性有限元分析

摘要：针对海底连续跨悬空管道的动力响应，本文摒弃传统欠精确的管跨两端固支处理方法，并基于弹性地基梁理论，考虑管线与海底土壤之间的非线性作用力，采用ANSYS有限元分析软件建立了管土耦合非线性有限元模型。与单跨海底悬空管道对比，讨论双跨管道的动力响应特性，分析得到双跨管道自振频率特性以及跨间管土耦合长度对管跨动力响应的影响规律，并进一步分析得到管道最大应力最小时的跨长与跨间管土耦合长度的比例关系，即管跨最安全的结构比例。分析结果对海底悬空管道的预防及治理，保障海底管道的安全运行具有较大的借鉴意义。

Nonlinear Finite Element Analysis of Dynamic Response of Suspended Submarine Pipeline with continuous spans

With the application of ANSYS finite element analysis software,a nonlinear finite element model of suspended submarine pipeline coupled with sea-floor soil is developed.Discarding the traditional and imprecise pipeline model with double clamped or simply supported ends,the model is founded on the theory of elastic foundation beam,in which the nonlinear effect between pipeline and sea-floor soil is considered.Comparing with the pipeline with single span,the dynamic response of pipeline with double continuous spans is discussed.The effect of coupled length of soil and pipe between spans on the dynamic response of pipeline is also analyzed.Further more,the proportional relation between span length and coupled length with lowest maximum stress of pipeline is gained,which means a safest structural proportion.The model fits the actual structure better,and the analysis is instructive for preventing and controlling the suspending of submarine pipeline.