论文部分内容阅读
针对超大跨径斜拉桥主梁轴压力过大的问题,提出了部分地锚交叉索斜拉桥方案。特殊的结构体系使得交叉索段主梁的整体受力、索-梁锚固构造、局部应力分布与常规斜拉桥不同,有必要对其进行全面的分析。以1 408 m部分地锚交叉索斜拉桥方案与1 408 m常规体系斜拉桥方案为基础,分别建立了整体梁单元模型以及主梁局部模型,在整体受力分析的基础上,进一步分析了扁平钢箱梁在拉索交叉锚固作用下的应力分布。结果表明,新体系斜拉桥相较常规体系斜拉桥主梁最大轴力削减了28.7%;交叉索段主梁锚固区最大Mises应力为108 MPa;拉索水平分力不再累积使得交叉索段主梁整体处于很低的应力水平。证明了新体系斜拉桥主梁受力的优越性以及新型交叉拉索索-梁锚固结构的合理性。
Aiming at the problem of excessive axial pressure on the main beam of the super long span cable-stayed bridge, a partial cable-stayed bridge with cross-anchor is proposed. The special structural system makes the overall stress of the main girder of the cable cross-section, cable-girder anchoring structure, local stress distribution different from the conventional cable-stayed bridge, it is necessary to conduct a comprehensive analysis. Based on the 1 408 m partially anchored cable-stayed bridge and the 1 408 m conventional system cable-stayed bridge scheme, a whole beam element model and a local beam model are established respectively. Based on the overall stress analysis, further analysis Stress distribution of flat steel box girder under cable anchorage. The results show that the new system cable-stayed bridge can reduce the maximum axial force of the main girder of the conventional cable-stayed bridge by 28.7%, the maximum Mises stress in the anchorage zone of the main girder of the cross-section cable is 108 MPa, Section of the main beam at a very low stress level. The superiority of the main girder of the new system cable-stayed bridge and the rationality of the new cross-girder-girder anchoring structure are proved.