黄冈公铁两用长江大桥斜拉索安装技术

Installation Techniques for Stay Cables of Huanggang Changjiang River Rail-cum-Road Bridge

黄冈公铁两用长江大桥主桥为双塔双索面钢桁梁斜拉桥,跨度布置为(81+243+567+243+81)m。每桥塔两侧各设置19对斜拉索,全桥共有斜拉索152根,对该桥斜拉索安装技术进行总结。采用全回转架梁吊机将整盘斜拉索吊至桥面;采用全回转架梁吊机配合桥面上固定式放索盘进行桥面展索;斜拉索总体挂设采用先塔后梁的方案,利用塔吊和塔顶吊架完成塔端挂设;采用卷扬机及滑车组进行斜拉索梁端牵引,牵引到位后进行锚固;梁端安装完成后,3～8号斜拉索直接进行塔内刚性牵引,9～19号斜拉索先进行塔内软牵引(最大软牵引力为1 200kN)再进行刚性牵引;按设计要求对斜拉索进行分级同步对称张拉。该桥全部4 000余吨斜拉索的安装在7个月内全部完成。

The main bridge of Huanggang Changjiang River Rail-cum-14oad 13nage is a steel truss girder cable-stayed bridge with double pylons, double cable planes and with span arrange-ment （81＋243＋567＋243＋81） m. On both sides of a pylon of the bridge, each 19 pairs of the stay cables are provided and for the whole bridge, there are totally 152 nos. of the cables. In this paper, the installation techniques for the cables are summarized. In the process of installation of the cables, the fully rotary deck crane was used to lift each reel of the cables to the bridge deck and the cables were stretched there by the fixed cable stretching reel with the aid of the deck crane. The installation scheme was that the cables on the pylons were installed first and those at the deck level were installed late. For the installation of the cables on the pylons, the tower cranes and the lifting frames at the tops of the pylons were used while for the installation of the cables at the deck level, the cables were hauled by the winches and pulley blocks. When the ca- bles were hauled in place, the cables were anchored and after the installation of the cables at the deck level was completed, the cables No. 3-8 were directly rigidly hauled in the pylons and the cables No. 9-19 were first softly （with maximum soft hauling force being 1 200 kN） and then rigidly hauled in the pylons. In compliance with the design requirements, the cables were syn-chronously and symmetrically tensioned in steps and the installation of the whole 4 00O t stay ca-bles of the bridge were finally completed within 7 months.