大跨度坦拱主拱钢混凝土组合节段施工阶段三维仿真分析

3D Simulation Analysis of Steel Concrete Composite Segment of Main Arch in Large-Span Flat Arch at Construction Stage

宁波市澄浪桥主桥是一大跨度坦拱桥,其主拱拱脚至水平拉索锚固区的节段为钢混凝土组合结构;该节段截面尺寸较大,拱肋结构施工时会受到混凝土水化热作用的影响。利用大型结构分析软件ANSYS分析钢混凝土拱肋节段的水化热效应、内预应力的作用效应。分析结果显示,在水化热效应和预应力作用下,钢拱肋和混凝土的应力是可控的,水化热作用下的钢拱截面变形很小,结构能够满足施工时的受力要求。

The main bridge of Ningbo Chenglang Bridge is a large-span flat arch bridge,and the segment from arch foot to horizontal cable anchor zone of its main arch adopts the steel concrete composite structure.The arch rib structure undergoes the effect caused by concrete hydration heat at construction stage,because of its oversize cross-section in dimension.This paper uses the structural analysis software ANSYS to analyze the concrete hydration heat effect on reinforced arch rib segment,and the pre-stressing effect inside of the segment as well.The finite element analysis results show that stresses in steel arch rib and concrete are controllable under the effect of hydration heat and pre-stressing,and the cross-section deformation of the steel arch rib is quite small under hydration heat;therefore,the structure can meet the requirements of its strength and stiffness at construction stage.