拱背增大截面法在双曲拱桥加固设计中的应用

Application of extrados section enlargement method in the reinforcement design of double arch bridge

结合常德澧县艳洲水闸工作桥(尾水渠桥)采用拱背加固改造的工程设计实例,阐述拱背加固方案在空腹式双曲拱桥上应用的技术原理和方案特点。通过采用Midas/Civil大型空间有限元分析软件对实施改造加固方案前、后的尾水渠桥(3×50m等截面悬链线空腹式双曲拱桥)进行结构计算,分析尾水渠桥主拱圈的内力和抗力效应的变化,证明实例工程中所采用拱背加固的设计思路是有效可行的。加固后可以对双曲拱桥主拱圈的承载能力进行结构补强,延长了双曲拱桥的服役年限,节约工程投资,为同类工程项目加固提供一种新的方案选择。

According to Changde LixianYanzhou sluice bridge(tail channel bridge)with extrados reinforcement design examples,the technology principle and scheme characteristic of back reinforcement scheme used in the hollow double arch bridge is presented.Through the reinforcement on the implementation of Midas Civil finite element software scheme before and after the tail channel bridge(3×50m constant section catenary double arch bridge)analysis of internal force and resistance effect of tail channel bridge main arch ring,the engineering example proves that arch reinforcement design is feasible and effective,the reinforcement can carry capacity of the main arch of the double arch bridge structure reinforcement,prolong the service life of the double arch bridge,save the project investment,and provide a new solution for similar project reinforcement.