兰合铁路刘家峡黄河特大桥主桥设计分析

刘家峡黄河特大桥是新建铁路兰州至合作线重点工程之一,该桥位于高烈度地震区,主桥采用(100+180+100)m连续刚构,有效解决了跨越黄河和公路立交问题,另外该桥桥高105m,是一典型的高墩大跨结构,增加了桥梁设计和施工控制的难度。概要介绍主桥梁部及主墩构造尺寸,依照划分的施工阶段进行静力计算,动力计算包括抗震设防水准及地震输入的确定、动力计算模型确定与结构动力特性分析,确定抗震性能目标与验算原则,对关键截面进行了纤维单元划分并进行地震响应及反应谱分析。计算结果显示该桥均能符合规范相关要求。

Design Analysis of Liujiaxia Yellow River Main Bridge on Lanzhou-Hezuo Railway

The Liujiaxia Yellow River Bridge is one of the key projects of newly built railway from Lanzhou to Hezuo. It is located in high seismic intensity region. The main bridge is( 100 +180 +100) m of continuous rigid frame to cross the Yellow River and highway interchange. The height of the pier is105 m,so the bridge has the typical characteristics of high pier and long-span,which add more difficulties in bridge design and construction control. This paper introduces the girder of main bridge and main pier size and conducts static calculation according to the construction phase. The Dynamic calculation includes the determination of earthquake fortification standard and earthquake input,determination of dynamic calculation model and the analysis of dynamic behavior of structure,the determination of anti-seismic performance target and verification principle. Fibrous unit division is made and seismic response and response spectrum analysis is carried out. The results show that the bridge meets relevant requirements of the code.