上跨铁路2×85 m预应力混凝土连续板-桁组合双层转体桥设计  

Design of 2×85 m Prestressed Concrete Continuous Slab-Truss Composite Double-Deck Swivel Bridge Spanning a Railway

作　　者：刘振标[1] 王蒙 王勇 杨学臻 陈辉 LIU Zhenbiao;WANG Meng;WANG Yong;YANG Xuezhen;CHEN Hui(China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China;China Railway Tenth Group Fourth Engineering Co.,Ltd.,Nanjing 210046,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,武汉430063 [2]中铁十局集团第四工程有限公司,南京210046

出　　处：《铁道标准设计》2024年第11期72-78,共7页Railway Standard Design

基　　金：中铁第四勘察设计院集团有限公司科技研发计划课题(2022K109,2022K111)。

摘　　要：莞番高速与环莞快速路共线段上跨广深铁路主桥为2×85 m双层桥面板-桁组合桥,该桥为国内首座预应力混凝土连续板-桁组合双层桥,采用转体法施工。下层桥面宽41.7 m,采用密横梁体系的肋板式混凝土梁,满足上跨铁路时对结构养护维修工作量小的要求;上层桥面宽37.9 m,采用“钢弦杆+正交异性钢桥面板”,降低转体质量;钢弦杆与混凝土肋板间以钢桁腹杆连接,避免混凝土腹板出现裂缝等问题。建立空间有限元模型对结构静力特性、抗震性能及转体施工阶段进行计算分析,结果表明:本桥钢主桁及下层混凝土梁应力、结构刚度均满足规范要求;下层采用混凝土结构,符合转体施工过程中的受力状态,最大悬臂阶段上缘仍有约4 MPa的应力储备,充分发挥了混凝土抗压性能好的优势,节省了钢材。研究结果可为双层桥上跨营运铁路的桥梁设计提供新思路。The main bridge of the shared section of Dongguan-Panyu Expressway and Dongguan Ring Road spans the Guangzhou-Shenzhen Railway and features a 2×85 m double-deck slab-truss composite bridge.This bridge was the first of its kind in China,employing a prestressed concrete continuous slab-truss composite structure with double decks,constructed using the swivel method.The lower deck,41.7 m wide,utilized a ribbed slab concrete beam system with closely spaced cross beams,minimizing maintenance demands during service over the railway.The upper deck,37.9 m wide,adopted a“steel tie rod+orthotropic steel deck”structure to reduce the swivel weight.Steel tie rods were connected to the concrete ribbed slab via steel truss diagonal members,which prevented cracking issues in the concrete web.A spatial finite element model was developed to analyze the static characteristics,seismic performance and swivel construction stage of the structure.The results showed that both the steel main truss and lower concrete beam met the stress and stiffness requirements of relevant standards.The lower decks concrete structure complied with the stress conditions during swivel construction,with a stress reserve of about 4 MPa at the top edge during the maximum cantilever stage,fully leveraging the compressive strength of concrete and saving steel materials.These findings provide new design insights for double-deck bridges spanning operating railways.

关 键 词：跨线桥 双层桥 板-桁组合结构 转体施工法 设计 

分 类 号：U24[交通运输工程—道路与铁道工程] U442.5[建筑科学—桥梁与隧道工程] U445.465