青弋江特大桥边跨现浇段支架结构分析

ANALYSIS OF THE BRACKET STRUCTURE OF THE CAST-IN-PLACE SECTION OF THE SIDE SPAN OF THE QINGYIJIANG GRAND BRIDGE

在特大型预应力混凝土连续悬浇梁桥施工阶段,工程面临边跨现浇段长度较大时,常规的托架法施工风险高,容易造成过渡墩存在偏载严重的现象。桥梁支架结构作为承载支撑体系的基础,其稳定性关系到整体桥梁的施工安全,设计强度和承载力对工程质量有较大影响。文中依托青弋江特大桥预应力悬浇梁的施工实例,运用MIDASCIVIL软件对支架结构立柱、分配梁、横梁及联系杆受力进行了数值模拟计算。结果表明数值计算得出的支架结构各项应力均在设计强度范围之内,均符合施工要求,并在青弋江特大桥工程施工中得到应用。

When the length of the side span cast-in-place section is long during the construction stage of a super large prestressed concrete continuous cantilever beam bridge,a significant eccentric load generates in the transition pier under the traditional bracket method,which has a high construction risk.The stability of the bridge support structure is correlated with the overall safety of the bridge's construction,which serves as the cornerstone of the bear⁃ing support system.Engineering quality is significantly influenced by design strength and bearing capacity.The nu⁃merical simulation computation is done using MIDAS CIVIL software.The prestressed cantilever casting beam of Qingyijiang Bridge is studied by the numerical simulation by using MIDAS CIVIL software,where the stress of the support structure's column,distribution beam,beam,and connecting rod is calculated.The results show that the stress in support structures is within the design strength range,meeting the requirements for construction of the Qin⁃gyijiang Bridge.