索塔锚固区缓粘结环向预应力施工关键技术

Key Construction Technology of Retard-bonded Circumferential Prestress in Cable Tower AnchorageZone

缓粘结预应力结合了无粘结预应力和有粘结预应力的优点,具有施工工艺简单、耐久性好、质量易于控制等优点,在工程施工中应用越来越广泛。文章结合跨襄阳北编组站大桥索塔锚固区环向预应力施工,对其施工过程中的难点进行阐述,并通过方案对比分析,详细介绍了缓粘结预应力的制作、安装、张拉、封锚等过程。目前,缓粘结预应力已成功在跨襄阳北编组站大桥主塔施工中应用,为后续类似斜拉桥索塔环向预应力施工提供了借鉴。

Retard-bonded prestressing combines the advantages of unbonded prestressing and bonded prestressing.It has the advantages of simple construction technology,good durability and easy quality control.It is more and more widely used in engineering construction.Based on the circumferential prestress construction of the cable tower anchorage zone of the bridge across Xiangyang North Marshalling Station,this paper expounds the difficulties in the construction process,and introduces in detail the process of making,installing,tensioning and sealing anchor of the retard-bonded prestress through the comparative analysis of the schemes.At present,the retard-bonded prestress has been successfully applied in the construction of the main tower of the bridge across Xiangyang North Marshalling Station,which provides a reference for the subsequent circumferential prestress construction of similar cable-stayed bridges.