独塔非对称自锚式悬索桥合理约束体系研究

Study on Reasonable Restraint System of Single-pylon Asymmetric Self-anchored Suspension Bridge

自锚式悬索桥通过主缆与加劲梁锚固结合的方式,形成闭合传力路径。主缆的水平分力通过锚固区逐渐传递到主跨加劲梁,竖向分力则主要通过边跨自重平衡。在静力情况下,主梁为超静定体系;在动力情况下,通常为全飘浮或者半飘浮体系来达到减隔震目的。这样就会造成主梁约束转变的情况,这个问题在独塔非对称自锚式悬索桥中尤为凸显。以太原市通达街跨汾河的四跨独塔非对称自锚式悬索桥为背景工程,建立全桥有限元模型,分析了全桥在静力及动力情况下不同约束体系对全桥受力的影响,为今后同类型结构设计提供依据。

The closed force transferring route of self-anchored suspension bridge is formed through the anchoring connection of the main cable and stiffening girder.The horizontal component force of the main cable is gradually transferred to the stiffening girder of the main span.The vertical component force is balanced mainly by the side span weight.The main girder is a statically indeterminate system under the static force condition,and under the dynamic condition,is usually the full-floating or semi-floating system in order to reach the purpose of seismic mitigation and absorption.This will result in a change in restraint system.This problem is particularly prominent in the single-pylon asymmetric self-anchored suspension bridge.Based on the four-span single-pylon asymmetric self-anchored suspension bridge across Fenhe River in Tongda Street of Taiyuan City,a finite element model of the whole bridge is established to analyze the influence of the different restraint systems on the stress of the whole bridge under the static and dynamic conditions,which provides the basis for the design of the similar structures in the future.