港珠澳大桥正交异性钢桥面板制作技术

Manufacturing Techniques for Orthotropic Steel Deck Plates of Hong Kong-Zhuhai-Macao Bridge

针对港珠澳大桥长寿命的设计要求,对桥面板U形肋加工技术及桥面板自动化焊接技术进行研究,分析如何通过提高U形肋与桥面板的焊接质量和稳定性来提高正交异性钢桥面板的抗疲劳性能。U形肋的加工工序为:钢板校平→预处理→钢板切割→边缘加工→钻孔→坡口加工→压型。U形肋的组装、定位焊在专用机床上完成,定位焊由焊接机器人完成,突破了制约U形肋焊接熔深难于达到设计要求80%的瓶颈及焊接质量不稳定的难题。采用船位焊接技术,保证了焊缝外观成型,使桥面板与U形肋间连接焊缝的焊趾过渡更加平顺,应力集中大大降低。对U形肋角焊缝进行疲劳试验,结果表明采用新工艺后U形肋焊缝的抗疲劳性能大幅提升。

To cater for the design requirements of long life of the Hong Kong-Zhuhai-Macao Bridge, the processing technique for the U ribs of the orthotropic steel deck plates and the auto- matic welding technique for the deck plates of the bridge were studied and the ways of how to im- prove the fatigue performance of the deck plates through improving the welding quality and weld- ing stability of the U ribs and deck plates were also analyzed. The processing procedures of the U ribs were those of the steel plate leveling → prehandling → steel plate cutting → edge trimming →drilling → groove processing → profiling. The assembling and tack welding of the U ribs were car- ried out on the special machine tools, of which the tack welding was implemented by the welding robots. The bottleneck that the penetration depth of the U rib welding was difficult to meet the 80 % penetration depth as required by the design was thus broken through and the problem that the welding quality was not stable was solved. The application of the flat position fillet welding tech- nique in the processing ensured the appearance, shapes and quality of the welding seams, which made the transition of the welding toes of the welding seams connecting the deck plates and U ribs still smoother and the stress concentration greatly reduced. The fatigue tests made for the fillet welding seams of the U ribs showed that the fatigue performance of the welding seams after appli- cation of a series of the new workmanship was greatly improved.