（江苏法尔胜缆索有限公司，江苏 江阴 214445）
摘 要：武汉青山长江公路大桥主桥为主跨938 m的双塔双索面全飘浮体系斜拉桥，采用平行钢丝（PWS）斜拉索，空间双索面扇形布置，全桥共252根，单根最长503.435 m、最重60.499 t。针对该桥超长、超大规格PWS斜拉索的安装牵引力大、牵引力控制难度大等难点，在考虑主梁刚度较低、牵引时塔梁锚固点坐标变化的情况下，提出了斜拉索牵引力优化计算方法，提高了计算精度；斜拉索采用软硬组合牵引方法施工（硬牵引采用1.6 m长的主拉杆＋1.0 m长的副拉杆，软牵引采用1束19根Φ15.24 mm、长25 m、软牵引力1 900 kN的钢绞线），经塔梁锚固结构张拉空间分析后选择在塔端牵引；主、边跨软硬组合牵引对称同步进行，并采用自动控制连续千斤顶作为软牵引动力设备，提高了施工效率。
中图分类号： U448.27；U445.4 文献标志码： A
Installation and Traction Techniques for Stay Cables of Qingshan Changjiang River Highway Bridge in Wuhan
WANG Zhi-gang, QIN Yong-xi, ZHOU Qiang-sheng, YAO Yong-feng, JIANG Hua
(Jiangsu Fasten Steel Cable Co., Ltd., Jiangyin 214445, China)
Abstract: The main bridge of Qingshan Changjiang River Highway Bridge in Wuhan, which has a main span of 938 m, is a two-pylon cable-stayed bridge of a full-floating system. The stay cables, made of parallel steel wires (PWS), are fanned out in spatial double cable planes. A number of 252 stay cables are tensioned, with the maximum length and weight reaching up to 503.435 m and 60.499 t, respectively. The very long and large-scale PWS stay cables pose great challenges to the installation as well as traction control due to the daunting traction force needed. Given that the stiffness of the main girder is low and the coordinates of the pylon-girder anchoring points would change in the traction process, a calculation method to optimize the traction forces for the stay cables was proposed, with intent to improve the computing accuracy. The stay cables were installed by the combined use of rigid traction and flexible traction, the former was carried out by using the 1.6 m-long main tensile rods and 1.0 m-long subsidiary tensile rods, while the latter was realized by using a 25 m-long steel rope consisting of 19, Φ15.24 mm steel strands, with a traction capacity of 1 900 kN. Considering the space for tensioning operation in the pylon-girder anchoring structure, the stay cables were dragged from the pylons. The rigid and flexible traction systems in the main and side spans worked in a synchronized and parallel manner, using the automatically-controlled continuous jacking system to power the flexible traction, as a result, the construction efficiency was improved.
Key words: cable-stayed bridge; parallel-steel-wire stay cable; installation traction technique; traction force calculation; combined traction; bridge construction