选择贵州省响水河大峡谷的特大型梁桥为实例研究对象,运用MIDAS/Civil有限元分析软件中的桥梁博士,分析计算了混凝土收缩徐变效应对大跨径预应力混凝土连续刚构桥的影响作用.研究结果表明:大跨径预应力混凝土连续刚构桥上部结构挠度在成桥运营阶段受混凝土收缩徐变效应的影响最大,且随着混凝土龄期的增长,混凝土收缩徐变效应不断提高,但增长速率随龄期增长而呈现下降趋势;悬臂梁根部截面顶板应力相较于截面底板应力更容易受到混凝土收缩徐变的影响作用,且这种收缩徐变往往在桥梁悬臂梁根部截面结构出现一个极大挠度值,导致桥梁结构出现变形,因此,实际工程设计施工中应充分考虑到混凝土收缩徐变对结构变形所带来的影响.%this article choose guizhou xiangshui river valley of super large bridge as an example the research object,using the finite element analysis software MIDAS/Civil in Dr Bridges,concrete shrinkage and creep effect are analyzed and calculated by the effect of long-span prestressed concrete continuous rigid frame bridge,the results show that the deflection of long-span prestressed concrete continuous rigid frame bridge upper structure in operation stages into a bridge under the influence of concrete shrinkage and creep effect is the largest,and locked along with the growth of the age of concrete,concrete shrinkage and creep to grow,but growth rate along with the age growth and a declining trend;Cantilever root section of roof stress compared with cross section slab stress are more susceptible to the influence of concrete shrinkage and creep effect,and the shrinkage and creep are often at cross section structure bridge cantilever root a maximum deflection value,lead to deformation of bridge structure,therefore,in practical engineering design and construction should fully consider the concrete shrinkage and creep on the effects of structural deformation.
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