纠偏位移控制法在大跨度钢管拱肋纵移中的应用研究  

Application of Deflection Deviation Rectifying and Control Method to Longitudinal Movement of Long-Span Steel Tubular Arch Rib

作　　者：周军伟 ZHOU Jun-wei(Yunnan-Guangxi Railway Guangxi Co.,Ltd.,Nanning 530022,China)

机构地区：[1]云桂铁路广西有限责任公司,广西南宁530022

出　　处：《桥梁建设》2022年第4期133-139,共7页Bridge Construction

摘　　要：为保证异位拼装的大跨度钢管拱桥拱肋在脱架、顶推纵移过程中线形、内力不偏离设计要求,提出一种纠偏位移控制法。该方法以位移偏差作为控制参数,采用单因素逆推法确定某一维度的纠偏荷载量值及类型,将其反向作用于施工状态下的拱肋,使发生偏移的结构恢复至设计初始位置,再于3个维度方向重复纠偏过程,以达到纠偏要求。以贵南高铁澄江双线特大桥加劲钢管拱肋施工为背景,建立拱肋脱架及纵移模型,经比选采用刚性支承张拉方案进行系杆张拉;基于所提出的纠偏位移控制法进行拱肋实际顶推纵移过程纠偏,以验证其纠偏效果。结果表明:由位移偏差逆推计算纵移过程中纠偏荷载,实现了横桥向及竖向精准纠偏,拱肋测点横桥向、竖向应力极值相对误差分别降低55.56%、27.72%,确保最终成拱线形光滑平顺,符合设计曲线,截面应力接近设计应力水平。A deflection deviation rectifying and control method is proposed,which is able to ensure the geometry and internal forces of the arch rib to meet the design requirements either in the scaffolding dismantling process or the incremental launching process of the long-span steel tubular arch rib that is assembled off site.Taking the deflection deviation as the control parameter,the single-factor reverse method is used to determine the volume and type of rectifying loads of a certain dimension,which is subsequently applied to the arch rib under construction in a reverse order to enable the deflected structure to return to its initial design position,then the deflection rectifying process is repeated in three dimensions to meet the rectifying requirements.The construction of the stiffening steel tubular arch rib of the Chengjiang River Bridge of Guiyang-Nanning High-speed Railway that accommodates double rails was referenced,based on which a model to simulate the scaffolding dismantling and longitudinal movement of the arch rib was built up.It was determined to tension the tie using a rigid supporting and tensioning method,and the dynamic deflection and internal forces of the arch rib were calculated.The proposed method was used to rectify the deflection deviation of the actual arch rib during its longitudinal moving process,by which the effectiveness of the method was verified.It is shown that by using the deflection deviation to reversely calculate the deflection loads during the longitudinal moving process of the arch rib,the accurate deflection rectifying of the arch rib in the transverse and vertical directions is achieved,with the relative errors of extreme stresses in the transverse and vertical directions reduced by 55.56%and 27.72%,respectively.The geometry of the completed arch rib is smooth and agrees well with the design geometry,and the stresses on a cross-section approximate the design level.

关 键 词：钢管拱桥 大跨度加劲拱肋 线形 纠偏位移控制法 顶推纵移 纠偏荷载 系杆张拉 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U445.4[交通运输工程—道路与铁道工程]