合龙顺序对V形墩连续刚构桥成桥状态影响的分析

The Analysis of V-Shape Pier Continuous Rigid Frame Bridge in Different Closure Order

大跨度连续刚构桥作为连续梁桥与T形刚构桥的结合形式,在合龙过程中由于预应力及墩形的影响,不同加载龄期的混凝土收缩徐变使得成桥线形和成桥应力差别很大,合理的合龙顺序可以更好的满足桥梁的使用要求.以三跨连续刚构桥为例,利用MIDAS/CIVIL大型有限元软件建立全桥模型,对施工阶段进行全过程分析,通过对不同合龙顺序下成桥线形、成桥内力以及墩顶最大位移三个方面的对比分析最终得到了合理可靠的的合龙方案,可以最大程度减少合龙顺序对桥梁后期挠度的影响,保证了合龙的合理性和准确性.

As a combination of continuous beam bridge and T-shape rigid frame bridge,large-span continuous rigid-frame bridge show great difference in the stress and bridge alignment because of the influence of prestress and different age of concrete shrinkage and creep. A reasonable closure order can meet the requirements of the bridge better. In this paper,large-scale finite element software MIDAS / civil was used to establish a model of three-span continuous rigid frame bridge and to analyze the whole process of the construction phase. By analyzing and comparing three aspects as bridge displacement,stress and the maximum displacement of the top of the pier,a reasonably reliable closure sequence can be got to decrease closure sequence＇s influence on bridge alignment and to ensure the rationality and accuracy of closure.