管桥耦合下管线悬索桥的动力特性和地震反应

为了研究管线悬索桥大直径管线和桥梁的耦合作用对结构动力特性和地震反应的影响,以澜沧江管线悬索桥为研究对象,利用有限元软件建立实桥模型,分析了管线悬索桥在管桥耦合作用下的动力特性,并研究了管桥耦合对桥梁地震反应的影响.结果表明,与未耦合时相比,管桥耦合作用下桥梁结构的自振周期较长,自振模态被激励的先后顺序发生变化;在地震波激励下,管桥耦合作用对管线悬索桥不同构件的受力和变形具有不同的影响,其中索塔顺桥向剪力和主梁横向位移均减小,主梁上弦杆轴力和竖向挠度均增大.在计算过程中考虑管桥耦合作用的影响能够比较真实地反映结构实际的动力特性.

Dynamic characteristics and seismic response of pipeline suspension bridge under pipe bridge coupling effect

In order to study the influence of coupling effect between large diameter pipeline and bridge of pipeline suspension bridge on the dynamic characteristics and seismic response of the structure, the Lantsang river pipeline suspension bridge was regarded as the research object, and the real bridge model was established with finite element software. The dynamic characteristics of pipeline suspension bridge under the pipe bridge coupling effect were analyzed, and the influence of pipe bridge coupling on the seismic response of the bridge was studied. The results indicate that compared with no pipe bridge coupling effect, the natural vibration period of the bridge structure is longer under the pipe bridge coupling effect, and the excited order of natural vibration modes changes. Under the excitation of seismic wave, the pipe bridge coupling effect has different influences on the force and deformation of different components. The shear force of cable pylon along the bridge and the lateral displacement of main girder decrease. However, the axial force of top chords and vertical deflection of main girder increase. The actual dynamic characteristics of the structure can be factually reflected through considering the pipe bridge coupling effect in the calculation process.