收缩徐变对拼宽桥梁影响的数值分析

Numerical Analysis on Influence of Shrinkage Creep on Spliced and Widened Bridge

由于混凝土收缩徐变的影响因素众多,且具有高度复杂性,为研究收缩徐变对拼宽桥梁的影响,以珠江路上的某小箱梁拼宽桥为研究背景,建立了空间梁格有限元模型。并从不同拼接方式、不同拼接时机来模拟收缩徐变对新老桥的受力影响。结果表明:收缩徐变作用下,靠近拼接处的新旧梁所受的内力最大,往两边依次减小,且随着搁置时间的延长,收缩徐变效应在减弱,可为类似扩宽桥梁对于拼接方式及时机的选择从受力角度提供借鉴。

Owing to many influence factors of concrete shrinkage creep with high complexity, in order to study the influence of shrinkage creep on the spliced widened bridge, and by the study background of a small-box beam spliced widened bridge on Zhujiang Road, the spatial beam grillage finite element model is set up to simulate the stress influence of shrinkage creep on the old and new bridges from the different splicing modes and the different splicing opportunities. The result shows that the internal force of the old and new beams near the splice is the maximum, and decreases in the both directions under the shrinkage creep, but with the extension of time, the shrinkage creep effect is weakened, which can be referred for the selection of splicing mode and splicing opportunity of the similar widened bridges from the angle of stress.