瓯江北口大桥南引桥顶升施工技术

Jacking Construction Technology for the South Approach Bridge of Oujiang River North Estuary Bridge

桥梁顶升技术作为一种有效的桥梁纠偏手段被广泛应用于桥梁线形调整方面。基于瓯江北口大桥南引桥第1联实际工程情况分析了该桥梁工程顶升施工的重难点,并依此建立适宜的桥梁顶升施工方案。采用理论计算与现场实测相结合的方法对顶升过程中箱梁的位移与应力进行有效监控分析,结果显示,该施工方案较好地指导了顶升施工。南引桥第1联各部位箱梁的实测顶升高度与设计顶升高度偏差均<10%。顶升过程中S02,S03号墩支座处梁体上缘呈受拉趋势,且未超过混凝土受拉强度,符合理论变化趋势。支座截面处箱梁应力变化规律与顶升高度变化规律相吻合。

Bridge jacking technology as an effective means of bridge deflection correction is widely used in bridge alignment adjustment.Based on the actual engineering situation of the first link of the south approach bridge of Oujiang River North Estuary Bridge,this paper analyzes the difficulties of the jacking construction of the bridge project and establishes a suitable bridge jacking construction program accordingly.Theoretical calculations and on-site measurements combined with the method of effective monitoring and analysis of the displacement and stress of the box girder in the jacking process are used,the results show that:The construction program is a good guide to the jacking construction.The measured jacking height of each part of box girder of the first link of the south approach bridge is deviated less than 10%from the designed jacking height.In jacking process,the upper edge of the girder at the support of No.S02 and No.S03 piers is tensile and does not exceed the tensile strength of concrete,which is in line with the theoretical trend.The change rule of box girder stress at bearing section coincides with the change rule of jacking height.