128m尼尔森体系提篮拱桥的施工控制

Construction Monitoring and Control of a 128-m Span Basket Handle Arch Bridge of Nielsen System

为了解尼尔森体系提篮拱桥在施工中的内力和线形状态是否满足设计要求,以合福高铁跨越合肥市包河大道的128m提篮拱桥为例,采用有限元软件MIDAS Civil进行尼尔森体系提篮拱桥的空间有限元计算分析,在施工控制中主要对系梁、拱肋的应力和线形以及吊杆的内力进行监测。监测结果表明,整个施工过程中系梁变形较小,拱肋的变形较为明显,两者在拆除系梁支架阶段的累计变形量与理论值均吻合较好;系梁与拱肋的应力水平均满足设计要求,处于安全合理的范围;吊杆内力测试结果与理论目标值相差均在±5%以内,满足设计要求。

To understand if the internal forces and geometric shape status of the basket handle arch bridge of Nielsen system can meet the design requirements in the construction process, the 128-m span basket handle arch bridge of the same type on the section of Hefei-Fuzhou HighSpeed Railway spanning the Baohe Avenue in Hefei City was cited as an example. The software MIDAS Civil was used to carry out the spatial finite element calculation and analysis of the bridge and the stress and geometric shapes of the tie beam and arch ribs and the internal forces of the hangers were mainly monitored and controlled in the construction. The results of the monitoring and control show that the deformation of the tie beam is little and the deformation of the arch ribs is obvious in the whole construction process. The accumulative deformation of the beam and ribs at the stage of removal of the tie beam supports is well agreeable with the theoretic values, both the stress levels of the beam and ribs can satisfy the design requirements and are in the safe and rational range. The differences between the measured internal forces of the hangers and the theoretic target values are within ±5 % and can satisfy the design requirements as well.