沙井河特大桥拱脚局部受力性能分析

Analysis on Local Mechanical Behavior of Arch Foot of Shajing Grand Bridge

钢管砼刚架系杆拱桥,结构受力通过拱肋传递至拱脚。拱脚结点要承受拱肋传来的内力和系杆力,同时由于在横梁上设置了横桥向预应力,所以拱脚结点受力十分复杂,因此有必要采用三维仿真分析的方法对拱脚局部应力进行研究。分析结果显示,该桥拱脚局部应力满足规范要求,但局部应力有改善的空间。最终采取相应构造改造措施,解决了局部点拉应力超标的问题。

For rigid frame tied-arch bridge with steel tube concrete,the structural stress is transmitted to the arch foot through the arch rib.The arch foot joint must bear the internal force and tied-bar force from the arch rib.At the same time,because the transverse pre-stressing force is set on the crossbeam,the stress of the arch foot joint is very complex.Therefore,it is necessary to study the local stress of the arch foot by means of three-dimensional simulation analysis.The analysis results show that the local stress of the arch foot of the bridge meets the requirements of the code,but there is room for improvement of the local stress.Finally,the corresponding structural measures are taken to resolve the problems of tension/stress at the local points exceeding the standards.