客运专线预应力混凝土桥梁徐变变形控制方法研究

为了研究混凝土收缩徐变对客运专线预应力混凝土连续梁桥后期变形的影响,选取合理的徐变系数,通过大型有限元软件Midas建立实桥模型,模拟施工全过程,对郑徐客运专线上的一座预应力混凝土连续梁桥的收缩徐变进行分析,得出了一些改善连续梁桥后期徐变变形的结论.结果表明:在不影响施工工期的情况下,延迟合拢时间有利于控制桥梁后期徐变变形;铺设二期恒载时,从边跨往中跨铺设或从中跨往边跨铺设都能减小由徐变引起的上拱;增加顶板束或减小底板束都将改善桥梁的上拱.

Control Method Research on Prestressed Concrete Bridge Creep Deformation of Passenger Dedicated Line

In order to study the influence of concrete shrinkage on late deformation of prestressed concrete continuous girder bridge of passenger line,this paper selects the reasonable creep coefficient to establish a bridge model through the large-scale finite element software Midas and simulates the construction process,analyzes the shrinkage of a prestressed concrete continuous girder bridge of ZhengXu passenger line and comes up with some conclusions to improve the late deformation of continuous girder bridge. The results show that. the time extension of bridge closure is beneficial to the control of bridge creep deformation under the circumstance of not delaying the construction period; When laying secondary dead load,it can both decrease creep on the arch to lay from the side span to the middle span or from the middle span to the side span; It can improve the arch of the bridge by increasing the prestressed roof or decreasing the prestressed floor.