郑州黄河公铁两用桥主桥第一联钢梁架设技术研究

郑州黄河公铁两用桥是目前世界上最长的公铁两用桥梁。其主桥第一联为(121+5×168+121)m六塔单索面钢桁结合梁斜拉桥,采用无断面联结系、无上平联的三主桁斜边桁空间桁架形式,结构新颖,施工难度大。由于其顶推长度长、重量重、跨度大等,经对架设方案的分析、研究和比较后,最终确定第一联钢桁梁采用多点同步顶推方法施工。该方案减少了高空作业和水上作业,有利于保证钢梁架设的安全、质量和施工进度,同时取消了常规方案中在黄河主河槽内设置的大型临时墩,既保证了施工期内黄河渡汛,又减少了后期河道的清理工作,经济效益和社会效益显著。

TECHNOLOGY OF STEEL TRUSS ERECTION OF THE FIRST SECTION OF THE MAIN BRIDGE ON ZHENGZHOU YELLOW RIVER HIGHWAY AND RAILWAY BRIDGE

Zhengzhou Yellow River Bridge is the longest railway and highway combined bridge in the world.The first section of the main bridge（121＋5×168＋121）m is 6-tower single-cable-plane cable-stayed bridge with steel truss and composite girder.Space truss with three main trusses and diagonal side truss is used,without cross brace or upper horizontal brace.This structure is novel,and erection is difficult.After strict analysis,research and comparison of the erection schemes,multi-point synchronic jacking scheme is used for the first section of the steel truss.The scheme reduces the high-altitude operations and marine operations,which will ensure the quality and safety of steel truss erection and construction progress.Additionally,temporary pier is not required in the main river channel,which can ensure that the Yellow River flood season will go smoothly,and also reduce the river cleaning after construction,which can bring remarkable economic and social benefits.