大中型悬索管道跨越结构清管动力响应分析

大中型管桥是油气输送管道系统中的关键部位，呈现高次超静定、高柔性的结构特点，清管过程中形成的积液将在管桥处产生强烈的冲击动载荷作用，破坏管桥结构的稳定性。考虑悬索管道跨越结构恒载产生的初始内力、拉索垂度等几何非线性因素，将塔架简化为变截面梁，建立了悬索管桥清管动力分析有限元模型。按照管桥积液流动具有的移动荷栽一时间历程的特性，采用荷载步施加移动载荷。结合实例分析了不同清管工况条件下悬索管桥跨越结构的振动位移、临界积液长度以及临界清管速度，从而为安全清管作业提供指导依据。

Study of the Dynamic Properties and Reaction Mechanism of the Large and Medium-span Suspending Cable Aerial Crossing Pipeline Structure in the process of Pigging

Engineering practice indicates that the long and middle-span aerial crossing engineering is the key part of an oil and gas transportation pipeline system, which has the structural features of high and super-static determinate and high flexibility. The overload of pigging will bring serious damage to it, and make the aerial crossing engineering malfunction. The aerial crossing engineering structure was simplified as a more-than-one-span structure with two fixed ends,by taking into consideration the effects of initial stress,cable droop,dimensional large displacement together. And the limited finite element models of pigging dynamic response were put forward in this paper. In terms of the characteristics of the moving load and the time course, the loading steps were adopted concerning the dynamic load on the aerial crossing engineering structure, and analyzes of the pigging dynamic characteristics of the aerial crossing pipeline were sequentially conducted. These steps are already used for calculating the vibration displacement, critical liquid length and pigging velocity in different working conditions,and can provide some instructions for pipeline pigging.