大跨径斜拉桥主梁选型及分析

Selection and Analysis on Main Girder of Long-span Cable-stayed Bridge

摘要:

首先基于积分法推导得到了斜拉桥各部件的造价和主梁应力计算公式，其次对比分析了5种不同主梁类型的斜拉桥技术及经济性，最后以传统组合梁斜拉桥为例进行参数分析。结果表明：采用UHPC材料代替传统的混凝土能极大地提高组合梁斜拉桥的极限跨径；主跨在300~750 m的斜拉桥主梁选用传统组合梁经济性最优，主跨在750~1 200 m时主梁选用钢箱梁经济性最优；斜拉桥的平方米造价指标随着桥宽的增加而相应减少；但对桥面以上塔高与跨径比的变化不敏感，经济合理的边中跨比和桥面以上塔高与跨径比分别在0.5和0.3左右。

Abstract:

The calculation formulas of each component cost and the main girder stress of cable-stayed bridge are deduced according to the integral method. The technologies and economies of five different girders of cable-stayed bridges are compared and analyzed. And the parameters are analyzed by the case of traditional composite girder cable-stayed bridge. The results show that the use of UHPC materials to replace the traditional concrete can greatly improve the limit span of the composite girder cable-stayed bridge. For the cable-stayed bridges with the main span of 300~750 m, the traditional composite girders are the most economical. When the main girder is 750~1 200 m, the steel box girder as for the main girder is the most economical. The square meter cost index of cable-stayed bridge decreases with the increase of bridge width. Bit it is insensitive to the change of pylon height to span ratio above the bridge deck. The economical and reasonable side to middle span ratio and the pylon height to span ratio above the bridge deck are about 0.5 and 0.3 respectively.