摘要
针对常规斜拉扣挂悬浇拱桥工期较长的问题,提出主拱圈与拱上立柱同步施工(简称拱柱同步施工)工艺。为研究该施工工艺的可行性,以某斜拉扣挂悬浇拱桥为背景,采用有限元法研究拱柱同步施工时悬浇阶段和拆索阶段的结构力学性能及稳定性,基于Newton-Raphson法分析几何与双重非线性因素对最不利稳定性工况的稳定性影响,同时进行拱柱同步、异步施工的索力及稳定性比较分析。结果表明:无论是否考虑风荷载,拱柱同步施工时主拱圈应力、扣塔偏位、结构稳定系数均满足规范要求;采用从扣塔顶往交界墩底先拆奇数索后拆偶数索的拆索顺序,能更好地优化结构力学性能及稳定性;拱柱同步施工大部分扣锚索索力较异步施工会有所增加,采用与拱柱异步施工同一索规格,其扣锚索安全系数仍大于规范限值2.0;拱柱同步施工的稳定系数低于拱柱异步施工,但远高于规范限值4.0,验证了拱柱同步施工的可行性。
This paper presents a parallel arch and spandrel columns construction method,which shortens the schedule of the conventional cable-stayed cantilever casting construction of an arch bridge.An arch bridge under construction was used as a case to study the feasibility of the presented method.The mechanical property and stability of the bridge at the cantilever casting stage and temporary cable demolition stage were numerically simulated.Based on the Newton-Raphson method,the stability of the structure under the most unfavorable condition was analyzed,considering the geometric and dual non-linear factors.The tensions of the temporary cables in the scenarios of arch-spandrel columns parallel and non-parallel construction were compared.The results demonstrate that the stresses in the arch,offset of temporary towers,and the stability factor of the structure in the arch-spandrel columns non-parallel construction all met the code requirements,no matter whether wind loads were considered or not.When the odd temporary cables were demolished ahead of the even temporary cables from the temporary towers towards the juncture piers,the mechanical property and stability of the structure were better modified.In the arch-spandrel columns parallel construction,the tensions of local temporary cables were greater than those in the arch-spandrel columns non-parallel construction,even when the temporary cables were with the same specs.The safety factor of the temporary cables is greater than the code-suggested value of 2.0.The stability factor of the bridge in the arch-spandrel columns parallel construction is lower than that in the non-parallel construction,but still far greater than the code-suggested value of 4.0,proving the feasibility of the arch-spandrel columns parallel construction.
作者
田仲初
陈俊岐
戴业
张伟
朱林
TIAN Zhongchu;CHEN Junqi;DAI Ye;ZHANG Wei;ZHU LIN(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;General Contracting and Operation Branch,China Communications Construction Co.,Ltd.,Beijing 100032,China)
出处
《世界桥梁》
北大核心
2025年第3期40-47,共8页
World Bridges
基金
国家自然科学基金项目(52078058)。
关键词
拱桥
斜拉扣挂法
悬臂浇筑
拱柱同步施工
力学性能
稳定性
有限元法
arch bridge
cable-stayed cantilever casting method
cantilever casting
arch-spandrel column parallel construction
mechanical property
stability
finite element method
