混凝土自锚式悬索桥收缩徐变效应分析

Shrinkage and Creep Effects Analysis of Concrete Self-anchored Suspension Bridge

为了研究混凝土收缩徐变效应对自锚式悬索桥力学性能的影响,将按龄期调整的有效模量法与有限元法相结合,采用有限元逐步计算法处理结构徐变问题,对混凝土自锚式悬索桥收缩徐变效应进行分析。结果表明,收缩徐变效应对其力学性能的影响主要是由于主缆锚固点在塔梁位置的改变而引起的结构线形及内力变化,主梁内的预应力损失较为显著,运营期主跨跨中主梁下缘压应力减小较大。自锚式悬索桥成桥合理状态应充分考虑收缩徐变效应对其力学性能的影响及合理设置主梁预拱度。

In order to study the shrinkage and creep effects of concrete on the mechanical properties of the self-anchored suspension bridge,according to the age adjusting effective modulus method combined with finite element method,the finite element gradual calculation method is used to analyse the shrinkage and creep effects on the self-anchored suspension bridge.Results show that the influence of shrinkage and creep effects on the mechanical properties of the self-anchored suspension bridge is mainly caused by the position change of the main cable anchorage points in the tower and beam,which leads to the change of the structural shape and internal forces,and loss of prestress of the main girder and stress of lower margin of the main span girder are significant,reasonable finished state of self-anchored suspension bridge should fully consider the influence of concrete shrinkage and creep effects on the mechanical properties and set the main beam camber properly.