超大拱式变截面渡槽收缩徐变影响研究

Shrinkage and Creep Analysis of Long Span Arched Flume with Variable Cross Section

以跨径200m的超大跨径变截面拱式渡槽的结构设计为例,通过建立有限元模型,对渡槽主拱圈的分段分环施工全过程进行了收缩徐变分析。结果表明,徐变收缩可引起较大的后期变形,对渡槽竖向位移影响显著。建议在超大跨拱式渡槽预拱度设计时,应充分考虑混凝土的收缩徐变对变形的影响,采取分段分环施工并在拱脚处使用微膨胀混凝土以减小收缩徐变的影响,并采取相应措施控制渡槽线形。

Shrinkage and creep analysis based on finite element method is conducted for a 200 m span arched reinforced concrete flume with variable cross section. The results show that shrinkage and creep of concrete can cause large long-term deformation and have significant impact on the vertical deformation of the flume. As a result, it is necessary to consider the effect of shrinkage and creep of concrete in the design of flume and take block points ring in construction. The slight expansive concrete is applied to reduce the influence of shrinkage and creep on the springing. Meanwhile some measures should be taken to control the deformation of flume.