系杆拱桥施工支架刚度对结构受力的影响分析

Analysis on Influence of Construction Support Stiffness on Structural Internal Force for Tied Arch Bridge

文章以1座采用少支架施工的系杆拱桥为背景,阐述了拱肋施工重量引起的系杆和支架整体变形以及支架基础沉降对系杆结构内力的影响,通过考虑少支架变形影响的施工过程模拟,进行了系杆内力的具体理论分析计算。结果表明,拱肋支架直接支撑在系杆上时,其自重作用将会减小系杆内的预应力效应,对系杆受力安全形成不利影响;拱肋支架直接支撑于系杆支架时,对系杆受力的影响要明显大于拱肋恒载先传至系杆的情况,因而更应引起设计、监控和施工方面的重视。

Taking a limited brackets construction tied arch bridge as the background,this paper describes the deformation of tied bar and brackets caused by the rib construction weight and the influence of brackets foundation settlement on tied structural internal force.Then the paper makes a specific theoretical analysis and calculation of the tied internal forces by construction process simulation considering the deformation of limited brackets.The results show that,when the rib brackets directly support the tied rod,its own weight will reduce the prestressing effect of the tied rod and make an adverse effect on the force security of the tied rod.When the rib brackets directly support the tied rod brackets,the impact on the force of tied rod is significantly greater than that the dead load of rib spread on the tied rod first,therefore,it should attract more attention of design,monitoring and construction.