滨州黄河公路大桥斜拉索安装工艺探究

Installation Craft Exploration of Stayed Cables for Binzhou Highway Bridge over Yellow River

滨州黄河公路大桥主桥为6跨连续PC箱梁三塔双索面斜拉桥,斜拉索为直径7mm的镀锌高强低松弛钢丝。斜拉索安装分为放索、安装、牵引、张拉4道工序。为保护斜拉索PE保护层,斜拉索吊装时采用尼龙绳,运输采用自制的运索平车,运索平车设有导向转盘,放缩盘增设刹车装置。在塔上安装大吨位的斜拉索时首次采用两道索夹牵引的方法,减小了导链引索的引力,有效避免了斜拉索的滑脱。斜拉索张拉分3次进行,第1次张拉时为避免引索时刮伤保护层,针对挂篮悬浇端和支架现浇端的特点,分别设计制作了挂篮端引索支撑架和现浇端引索支撑架。斜拉索安装工艺改进后,有效地保护了斜拉索层,提高了工作效率和安全性。

The main bridge of Binzhou Highway Bridge over Yellow River is a cable-stayed bridge with six-spans of continuous box girder, triple towers and double cable planes, its stayed cables are 7 mm in diameter of zinc-covered high strengthening low-relax steel wires. The installation of stayed cables consists of discharging cables, fixing, draught and tensioning. For protecting stayed cables, nylon ropes are adopted when PE cables are erected, self-made vehicle with leading-guide turn table is adopted when transported, and braking device is set on discharging-shrinking table additionally. A method of two cable-nip traction is first applied when large tonnage cables are installed, all these decrease draught force of leading chain, and avoid surging for stayed cable efficiently. Tensioning of stayed cable is carried into execution for 3 times. On first time, for sake of no scraping the protecting layer of stayed cables, hanging basket-supporting legs and casting inhaul frames are made according to their construction characteristic. Technic improvements in process of stayed cable installation efficiently protect PE cable, and enhance work efficiency and security.