上跨铁路钢箱梁桥顶推施工主梁水平线形监测分析

Analysis on Horizontal Alignment Monitoring of the Main Beam During the Incremental Launching Construction of the Steel Box Girder Bridge Overcrossing Railway

钢箱梁的线形精度是顶推施工质量控制的关键。钢箱梁顶推施工过程中,主梁移动会引起钢箱梁、导梁、桥墩等应力、变形不断发生变化,需要及时监测与纠偏主梁。文章以常州市奔发路跨高速铁路钢箱梁顶推施工为工程背景,利用自主研发的安全监测平台,结合有限元模拟分析,对该工程钢箱梁顶推施工中的主梁水平线形进行远程自动化实时监测,并作出偏位分析,指导纠偏策略。结果表明,施工过程中结构存在一定的偏位,但仍处于可控范围;主梁的头部偏位幅度明显大于尾部偏位,需要针对头部结构重点采取相应的纠偏措施。

The alignment accuracy of steel box girder is the key to the quality control of incremental launching construction.During the incremental launching construction of steel box girder,the movement of main beam will cause the stress and deformation of steel box girder,guide beam and pier to change constantly,so it is necessary to monitor and correct the deviation of the main beam in time.Based on the incremental launching construction of the steel box girder of Changzhou Benfa Road overcrossing the highspeed railway,combined with the finite element simulation analysis,this paper uses the self-developed safety monitoring platform to carry out remote automatic real-time monitoring of the horizontal alignment of the main beam in the incremental launching construction of the steel box girder of the engineering,and makes the deviation analysis to guide the deviation correction strategy.The results show that there is a certain degree of structural deviation during the construction process,but it is still in the controllable range;the deviation amplitude of the head of the main beam is obviously larger than that of the tail,and corresponding correction measures should be taken specifically for the head structure.