兰州中山桥桥墩外钢围堰施工关键技术

Key Construction Techniques for Steel Cofferdam External Piers of Lanzhou Zhongshan Bridge

为更好地保护古建筑兰州中山桥,提高桥墩的抗震能力及耐久性,提出了钢围堰干作业法外包混凝土加固桥墩技术。在剖析中山桥桥墩外围钢围堰施工的重点、难点的基础上,通过计算分析定量设计了钢围堰结构,研究了桥墩外黄河卵石覆盖层开挖、钢围堰悬空安装及钢围堰封底施工等3项关键技术。

To better protect the Zhongshan Bridge that is a state-owned antiquity, as well as improved the seismic performance and durability of the piers of Zhongshan Bridge, this paper introduced the strengthening technique of bridge piers by external concreting with the assistance of steel cofferdam. Based on the analysis of the key and difficult points of the steel cofferdam work, through computation and analysis, the paper gave the quantitative designs of steel cofferdam structure and introduced three key techniques in the steel cofferdam work which included excavating the cobble layer in Yellow River, installing the steel cofferdam in a suspended manner and bottom concrete casting for the cofferdam, and also carried out the loading analysis to the steel cofferdam, which is to the reference purpose for same construction activities.