提高PC三塔斜拉桥整体刚度研究

Study on Improving the Whole Rigidity of Prestressed Concrete Three-pylon Cable-stayed Spans

三塔斜拉桥由于中间塔顶没有端锚索来限制它的水平变位,使得柔性结构斜拉桥的柔性进一步增大,随之而来的是变形过大,整体刚度不能满足容许变形的要求.结合某长江大桥一三塔斜拉桥方案进行研究,借助已有改善多塔斜拉桥刚度的方法,通过M IDAS计算分析对比,得出最适合此长江大桥刚度的改进方法,对其它地区三塔斜拉桥的刚度改进方法有一定的借鉴作用.

The intermediate pylon of three-pylon cable-stayed spans lacks back-stays to limit its longitudinal displacement, which makes the structure more flexible. As a result ,its deformation is so considerable that the whole structure＇s rigidity fails to the request of deformation tolerance. According to the analysis of a blue print of a three-pylon cable-stayed bridge across the Changjiang River with the finite element software MIDAS, making use of the available methods at present, a suitable method to improve the rigidity of this three-pylon cable-stayed spans is brought forth, which can be applied in other constradions like this.