超大跨度悬索桥主梁架设顺序研究

Analysis on Girder Erection Sequence of Super Large-span Suspension Bridge

悬索桥是目前世界上跨越能力最优的桥型,而其主梁的架设是整个桥梁施工过程中最为关键的环节,需考虑安装顺序、架设方法、架设单元和连接方式等诸多因素,而主梁架设顺序是首先要分析确定的要素。以某超大跨度悬索桥为例,对由跨中至桥塔架设和由桥塔至跨中架设两种传统的不同架设顺序进行研究。通过建立有限元模型,以主缆标高变化大小、桥塔侧主缆平切角大小、主缆与桥塔净距、索夹处主缆折角大小、索夹抗滑移安全系数、下弦杆开口间距、加劲梁线形变化等因素对悬索桥结构内力、位移的影响进行对比分析,最终推荐由跨中至桥塔架设主梁的顺序。

Suspension bridge is the best spanning-ability bridge type in the world,and the erection of main girder is the key link in the whole construction process.Erection order,erection method,erection unit and connection mode are considered in the erection of the main beam,and erection order is the primary analysis factor.Taking a super large-span suspension bridge as an example,two different traditional erection orders were analyzed:one was from the mid span to the bridge tower,and the other was from the bridge tower to the mid span.By establishing the finite element model and comparing the reference factors,such as the change of the main cable elevation,the horizontal cutting angle of main cable at bridge tower side,the clear distance between the main cable and the bridge tower,the folding angle of the main cable at the clamps,opening distance of lower chord,linear change of stiffening girder,it was clear that the super large-span suspension bridge was suitable for erecting from the mid span to the bridge tower.