银川滨河黄河大桥主桥钢梁顶推施工方案研究与创新

Research and Innovation of Steel Beam Pushing Construction Scheme for Main Bridge of Yinchuan Binhe Yellow River Bridge

银川滨河黄河大桥主桥长612m,为目前跨径最大的多塔连跨钢混叠合梁自锚式悬索桥。主桥上部结构主梁为钢-混凝土叠合梁,梁宽41.5m,采用先梁后缆的施工方案。钢梁采用了单向多点步履式同步顶推与支架拼装相结合的钢梁安装方案,该方案针对黄河夏季汛期冲刷大(达4～6m),冬季冰凌水平撞击力大、顶推距离长、钢梁双向纵坡对拼装与顶推线形精度要求高、施工工期紧、存在冬季低温下钢梁焊接与顶推等特点,较常规的钢梁顶推施工方法有较大的提升和创新。

The overall length of Binhe yellow river bridge in Yinchuan city is 612 m,so far it is the largest suspension bridge of 4-span with 3 towers.The superstructure type is steel-concrete composited girder and is 41.5 m in width.Construction sequence is from girder to main cable.Two installation methods are used for the girders’construction,one is walking incremental launching of one-way and multiple-point,another is assembling girder with scaffolding.There are many problems need to be solved in this project,great river wash in summer time(up to 4~6 m),large horizontal ice impact force in winter time,long walking distance,high accuracy due to longitudinal slope in both sides,construction period is limit,incremental launching construction and welding work during winter with low temperature,etc.The methods used in this project are promoted and innovated comparing to ordinary incremental launching construction.