兰州市小西湖黄河大桥设计参数分析与优化

Design Parameter Analysis and Optimization of Xiaoxihu Yellow River Bridge in Lanzhou City

通过兰州市小西湖黄河大桥的设计,论述了部分斜拉桥孔跨的布置和梁高的选取;指出了塔高的决定除在技术经济上把握以外,还应考虑景观的需要,并通过受力计算确定了斜拉索的根数、索间距及无索区的长度;建立了以主梁弯曲应变能为目标函数,对斜拉索的初张力进行了优化分析,使结构受力行为达到最优.从而阐明了部分斜拉桥设计参数的选取过程.

In this paper, through the design of Xiaoxihu Yellow River Bridge in Lanzhou,the disposal of span and choice of the beam height were discussed about partial cable-stayed bridge. It was pointed out that the height of tower should take sight effect into account except the technology and economy. The number of cable,the distance between cable and the length of non-stayed cable segment should be calculated through force analysis. Basing on the bending strain energy of main beam as objective parameters,preliminary tension of cable was optimized. This made the stress character of structure best. So the process of design parameter choice was illustrated about partial cable-stayed bridge.