万宁2号特大桥预应力混凝土系杆拱施工中的特殊技术措施

Special Technical Measures for the Construction of the Reinforced Concrete Tie Arch of the 2nd Mega Bridge at Wanning

万宁2号特大桥有一孔61.5m预应力混凝土系杆拱,在系杆拱桥施工时需通过JQ900A型架桥机和KSC900型运梁车,因此系杆拱的拱肋、横撑要等到后续孔的运梁、架梁工作完成以后才能施工。故在施工中采取调整工序,在箱梁梁体的跨中增加临时支墩(保证架桥机、运梁车等重型荷载作用在梁体上而不会导致箱梁的破坏)、系杆拱桥箱梁梁体的预应力体系进行二次分配等一系列技术措施来保证施工目的实现,确保了安全、保质、按期地完成施工任务。

The 2nd Mega Bridge at Wanning contains a 61. 5m reinforced concrete tie arch, during the construction of which Type-JQg00A Bridge Erector and Type-KSC900 Beam-moving Cart have to go through it, in which case the construction sequences of it have to be changed,namely,the construction of the arch rib and the lateral brace of the tie arch has to be put off until the moving and erecting of the beams of the following spans are completed. At the middle of the body of the box girder, temporary supports are provided to protect the box girder from being damaged when the heavy loads of the bridge erector and the beam-moving cart are exerted on it. A series of other technical measures, such as the reinforcing system of the box girder and the tie arch being re-distributed, is also taken to ensure the realisation of the construction purposes, as a result of which the construction tasks are finished safely, with good quality and as scheduled.