温度效应对CFST拱桥拱肋预拱度取值影响的探讨

Discussion on the influence of temperature effect on the pre-camber value of CFST arch bridge arch ribs

为探讨制作温差对拱肋预拱度取值的影响,以某主跨528 m的中承式钢管混凝土拱桥为依托背景,利用MIDAS/civil建立有限元仿真模型,分析了五个不同制作温差梯度对拱肋成拱线形的影响。计算结果表明:当拱肋制作温差与设计基准温度相差较大时,原设计预拱度可能存在设置不足的情况,建议拱肋预拱度取值应计入拱肋制作温差对成拱线形的影响。此外,依据9座钢管混凝土拱桥实例,在有限元计算结果的基础之上结合Plane函数和Levenberg-Marquardt优化算法,得到了单位环境变温与空钢管状态下拱顶挠度间的显式函数关系式。

In order to explore the influence of temperature difference on the pre-camber value of arch ribs,this article takes a 528 m main span through steel tube concrete arch bridge as the background,establishes a finite element simulation model using MIDAS/Civil,and analyzes the influence of five different temperature difference gradients on the arch rib arch shape.The calculation results indicate that when the temperature difference between the arch rib production and the design reference temperature is significant,there may be insufficient settings for the original design pre-arch degree.It is recommended that the value of the arch rib pre-arch degree should be taken into account the influence of the arch rib production temperature difference on the arch shape.In addition,based on 9 concrete-filled steel tube arch bridges and finite element calculation results,combined with the Plane function and Levenberg-Marquardt optimization algorithm,an explicit functional relationship between unit environmental temperature variation and arch deflection under empty steel tube state was obtained.