沪通长江大桥大节段连续钢桁梁制造预拱度控制工艺研究

Study on precamber control technology in manufacturing large section continuous steel truss of Hutong Yangtze River Bridge

大节段钢桁梁整体制造与架设工艺的进步,保障了我国钢桥可以更多地采用大型化、整体化的方式进行设计与建造。然而,大节段连续钢桁梁空间构形复杂,特别是包含整体节点后的弦杆刚度大,对拼装线形控制提出很高的要求。在沪通长江大桥的钢梁制造中,为控制大节段连续钢桁梁在恒载作用下的挠度,保证钢桁梁在制造过程实现预拱线形,提出了针对整体双节点弦杆制作、三维测控网和整体大节段拼装的系列精度控制工艺措施,最终保障了沪通长江大桥的高精度合龙。本文提出的工艺措施可为类似钢桁梁厂制预拱度的高精度控制,提供理论依据和实践参考。

The progress of integral manufacturing and erection technology of large section steel truss girder ensures that more large-scale and integrated methods can be used for design and construction of steel bridges in China.However,the spatial configuration of large segment continuous steel truss is complex,especially the chord stiffness including integral joints is large,which puts forward high requirements for assembly alignment control.In the steel truss girder manufacturing of Hutong Yangtze River Bridge,in order to control the deflection of large section continuous steel truss girder under dead load and ensure the precamber of steel truss girder in the manufacturing process,a series of precision control measures for the production of integral double node chord,three-dimensional measurement and control network and integral large section assembly is put forward,which finally ensures the highprecision closure of Hutong Yangtze River Bridge.This paper can provide theoretical basis and practical reference for the high-precision control of precamber of similar steel truss girders.