独塔悬索桥基本参数研究

基于挠度理论以及等代梁法，分析矢跨比和高跨比对主缆和索塔用量的经济性影响和结构受力变形的影响，得出矢跨比和高跨比在经济性和结构刚度方面的各自适用范围.为验证建议范围内的矢跨比和高跨比可以满足结构经济性的同时亦满足结构的受力变形要求，试设计一座独塔双主跨悬索桥，并与中国某三塔悬索桥进行比较分析.结果表明：独塔悬索桥主缆用量比三塔悬索桥减少约14%，索塔造价减少约3.5%活载作用下独塔悬索桥主梁最大挠跨比、主梁最大转角以及塔顶最大纵向位移均小于三塔悬索桥.选择合适的矢跨比和高跨比的独塔悬索桥，可以兼顾结构的经济性和使用性，还可与三塔悬索桥方案竞争.

Research on Suspension Bridges with a Single-tower

Based on the deflection theory and equal-substitute beam method, the reasonable rise-span ratio and height-span ratio were suggested.A single-tower suspension bridge was designed according to the proposed rise-span ratio and height-span ratio, and was compared with a three-tower suspension bridge.According to the results, the number of main cables and the tower''s construction cost of a single-tower suspension bridge reduced by 14% and 3.5%, respectively, as compared with a three-tower suspension bridge.The ratio of deflection to span, the maximum rotation angle of the main girder and the longitudinal displacement of the tower top in a single-tower suspension bridge are lower than that computed for a three-tower suspension bridge separately under live load.Therefore, a single-tower suspension bridge is more economical and competitive, compared with three-tower suspension bridges.