沈阳市三好桥钢拱塔拉索施工关键技术研究

The Study on Shenyang Sanhao Bridge Steel Arch Tala Cable-Stayed Construction Key Technologies

目的系统研究斜拉索和水平索组成的混合体系斜拉桥的拉索张拉方法、施工工艺及施工关键技术.方法以沈阳市三好桥拉索施工为研究对象,针对由斜拉索和水平索组成的混合体系相互影响的特点,从理论上分析钢绞线拉力均值性和索力之间的关系.结果导出控制等值张拉法的张力计算公式.三好桥拉索施工关键技术为:首先进行水平索施工,一侧水平索先张拉到90%的初索力,待另一侧同索号的水平索安装初张拉后,两根水平索同时张拉至100%的初张拉力,水平索全部张拉完成后,再进行斜拉索的施工.结论对于钢拱塔斜拉桥拉索施工,需要处理好水平拉索的安装张拉带来的低应力锚固状态不利问题,把握住先水平索张拉,再进行斜拉索张拉的关键技术,混合体系索才能安装成功.

The cable tensioning method, construction technology and construction＇s key technology of mixed system of cable-stayed bridge composed of cable-stayed and horizontal cable are studied. In this paper, Shenyang Sanhao Bridge cable construction is taken as the research object. On the account of the interaction characteristics of the mixed system cable of the cable-stayed and level and from the theoretical viewpoint, the relationship between the strand pulling force mean and the cable force are analyzed. Then the export control laws equivalent tension calculation formula can be got. The key construction technologies of the Sanhao Bridge cables are： Firstly, horizontal cable construction. Secondly, one side of the level of pre-tensioned cable pull 90% of the initial cable force until the other side of the issue of the level of the same cable is installed in early tension,the two levels of cable tension at the same time pull up to 100% of the initial tension. Finally, the level of all the tension cable is completed;the construction of cable-stayed can be furthered. For the steel tower cable-stayed bridge cable-arch construction, the negative anchoring problem of the low stress state caused by the level of cable tension need deal with. If the key technologies are grasped that the first level of cable is tensioned firstly, and then the cable-stayed and the mixed-system cable can be installed successfully.