斜拉桥长索软硬组合牵引受力机理研究

Mechanism of the Combination of Soft-pulling and Hard-puling for Installation of Long Cable in Cable-stayed Bridge

采用软硬组合牵引的方法完成斜拉索的梁端牵引锚固在我国斜拉索架设施工中的应用尚属首次,有必要对其牵引受力机理进行研究,以确定其可行性和合理性。文章对苏通大桥长索牵引过程进行仿真分析,研究了张拉杆角度调整对整个牵引系统的影响,以及牵引过程中手拉葫芦不同程度失效导致张拉杆被索道管卡住的情况下张拉杆拉弯状态下的安全性进行了分析。分析认为,采用这种施工方式能够充分发挥软牵引与硬牵引的各自优势。硬牵引减小了软牵引力,将软牵引钢绞线数量减少,使软牵引钢绞线受力均匀性更容易控制,降低了软牵引的施工风险与难度,软牵引的使用又可以缩短硬牵引长度,降低硬牵引风险。

It＇s the first time that the stay cables on the pylon are installed with the combination of soft pulling and hard puling in China.It is necessary to research the mechanism of to determine its feasibility and rationality.In this paper,the process of cable installing in Su-tong Bridge is simulated.The effect of the angle adjustment of tension rod on the traction system is analyzed,as well as the reliability of tension rod in the state of bending causing by the failure of manual hoist.The results show that the soft and hard cable hauling method can utilize both advantages of soft-pulling and hard-puling.Due to the adoption of hard-pulling,tension force of soft-pulling falls,which result in reduction of steel twisted wires and make it easy to control.At same time,the adoption of soft-pulling could also shorten the length of hard-pulling,which leads to lower construction risk of hard-pulling.