摘要
新建北同蒲铁路韩家岭至应县增建四线工程中,朔州至山阴联络线上跨既有铁路桥梁为(32+48+32)m的变曲率小半径曲线预应力混凝土连续梁,受上跨铁路要求,设计首次采用整体顶推施工。文章重点介绍了跨既有铁路段变曲率小半径曲线梁顶推过程中,千斤顶、锚拉器、预应力钢束的布置,顶推方向、顶推稳定性的施工控制,以及导梁、主梁的检算分析。主要研究结论包括:(1)主梁截面采用单箱单室直腹板,水平千斤顶ZLD100型沿曲线梁顶推轨迹割线方向布置;(2)导梁分阶段制造,采用以折代曲的方式适应曲线变化;(3)支座中心距取3m满足施工和运营阶段抗倾覆稳定性要求;(4)曲线梁采取下坡顶进,有利于控制顶进方向和降低落梁高差;(5)利用Midas软件对曲线梁走行过程中导梁和主梁进行应力分析、横弯分析和局部分析,结果满足规范要求。
Shuozhou-Shanyin connecting line in the new four-line project of Hanjialing-Yingxian line is across the existing railway.The overpass bridge is（32 ＋ 48 ＋ 32） m prestressed concrete continuous beam with variable curvature and small radius.According to the requirements of the existing railway,incremental launching construction is first adopted in the design.This paper focuses on the layout of jack,anchor and prestressed tendon,the incremental launching direction,the construction control of incremental launching stability and the checkup analysis of guide beam and main beam during the incremental launching construction of curved continuous beam with variable curvature and small radius.The main research conclusions include that the single box,single chamber and straight-web shall be used for main beam section and ZLD100 type horizontal jack shall be arranged along the secant direction of incremental launching track of curved beam; the guide beam shall be made by stages and is adapted to the curve change by broken line instead of curve; The center distance of the support shall be 3 m so as to meet the requirements of anti-overturning stability at the stage of construction and operations; it is advantageous to control the jacking direction and reduce the height difference of falling beam by taking the downhill jacking; the analysis has been on stress,transverse bending and locality of main beam and guide beam by universal finite element software MIDAS and the result is satisfied with the requirements in the Code.
出处
《高速铁路技术》
2017年第6期56-61,77,共7页
High Speed Railway Technology
关键词
变曲率小半径桥
顶推施工
关键技术分析
variable curvature and small radius bridge
incremental launching construction
key problem analysis
