京雄高速跨永定河大桥局部构造体系对比研究  

Local Structural System Selection for Bridge Carrying Beijing-Xiong′anExpressway over Yongding River

作　　者：彭亚东 何维利 杨冰 潘迪 PENG Yadong;HE Weili;YANG Bing;PAN Di(Beijing General Municipal Engineering Design&Research Institute Co.,Ltd.,Beijing 100082,China)

机构地区：[1]北京市市政工程设计研究总院有限公司,北京100082

出　　处：《世界桥梁》2023年第5期76-81,共6页World Bridges

基　　金：国家自然科学基金项目(61860206013)。

摘　　要：京雄高速跨永定河大桥主桥为主跨300 m的中承式飞燕系杆拱桥。为确定合理的局部构造体系,结合该桥河道行洪和景观要求,提出4种局部构造体系:三跨固结体系、三跨活动体系、五跨固结体系和五跨活动体系,分别通过静力和动力时程分析,对比4种局部构造体系的受力和变形特点。结果表明:静力荷载作用下,三跨体系在边拱拱顶产生了很大的纵向弯矩,而五跨体系由于有辅助跨的平衡,主梁恒载产生的负弯矩较小,故其边拱拱顶和拱脚的弯矩均较小;E2地震作用下,五跨固结体系的主墩桩基轴拉力、主拱拱脚纵向弯矩、边拱拱顶和拱脚的横向弯矩明显小于五跨活动体系,且五跨固结体系在地震作用下的主梁位移也明显偏小;最终选取五跨固结体系为该桥局部构造体系。The bridge carrying the Beijing-Xiong′an Expressway over Yongding River is a half-through tied-arch bridge with a main span of 300 m,featuring its flying-bird-type steel box arch ribs.To accommodate the flood diversion of the waterway and landscaping requirements,four types of local structural systems were compared,including the fixed three-span system,three-span system with bearings,fixed five-span system,and five-span system with bearings.Static and dynamic time-history analyses were conducted to analyze the load bearing behaviors and deformation characteristics of the four local structural systems.The results show that under static loads,there exists great longitudinal bending moments at the crowns of side arches in the three-span system,while in the five-span system,due to the balancing effect of auxiliary spans,the hogging moment induced by the dead loads of main girder is relatively smaller,correspondingly,the bending moments at the crowns of side arches and arch springing are smaller.Under E2 earthquakes,the axle tensile forces in the piles supporting the main piers,longitudinal bending moments at the main arch springing as well as the transverse bending moments at the crowns and springing of side arches are obviously smaller than those of the five-span system with bearings.In addition,the deck displacement of the fixed five-span system under the action of earthquakes are obviously smaller,finally,the fixed five-span system was selected for the bridge.

关 键 词：中承式系杆拱桥 局部构造体系 静力分析 动力时程分析 有限元法 桥梁设计 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U442.5[交通运输工程—道路与铁道工程]