连续钢桁架桥中跨临时墩设置位置研究

Study on Setup Position of Temporary Pier for Midspan of Continuous Steel Truss Bridge

连续钢桁架桥采用中跨桁架节段悬臂拼装施工时,对设置中跨临时墩与结构受力性能的关系进行了研究。分析表明:设置中跨临时墩可明显减小最大悬臂状态下的结构竖向挠度;随着临时墩向跨中方向移动,结构竖向挠度、临时墩支反力及其下部基础规模逐渐减小,而中跨跨中弦杆轴力逐渐增加;临时墩位置对中支点弦杆轴力影响很小。

The continuous steel truss bridge is constructed by the cantilever assembly of midspan truss segment. The article studies the relationship of setting up the temporary pier of midspan and the stress performance of structure. The study shows that the setup of the temporary pier for midspan can obviously decrease the vertical deflection of structure under the maximum cantilever state. With the temporary pier moving to the midspan, the vertical deflection of structure, the bearing reaction of temporary pier and the scale of its lower base are gradually decreased, but the axial force of the chord member in the middle span is gradually increased. The influence of temporary pier position is little on this axial force.