论文部分内容阅读
大中型管桥常常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会在管桥处产生强烈的冲击动载荷作用而破坏管桥结构的稳定性。为此,考虑斜拉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,建立了斜拉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载时间历程的特性,采用荷载步施加动载荷。结合实例分析了不同清管工况条件下斜拉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,从而为现场安全清管作业提供了依据。
Large and medium-sized pipe bridges are often the key parts of oil and gas pipeline system, showing high-order statically indeterminate, highly flexible structural features, the formation of the liquid during pipe cleaning will have a strong impact in the pipe bridge dynamic load damage Tube bridge structure stability. Therefore, considering the geometric nonlinear factors such as the initial internal force and the dip of the cable due to the constant load of the cable stayed bridge, the tower is simplified as a variable cross-section beam, and the dynamic analysis finite element model . According to the characteristic of the moving load time history of fluid flow in the bridge, the load step is used to add the dynamic load. The vibration displacement, the length of critical effusion and the critical velocity of pigging across the structure of the cable-stayed bridge under different conditions of pigging were analyzed with examples to provide a basis for the safe pigging operation on site.