以白沙洲大道改造工程为例分析现状快速路改造的设计要点

Taking the Reconstruction Project of Baishazhou Avenue as an Example to Analyze Design Points of Current Expressway Reconstruction

以白沙洲大道改造工程设计为例,提出快速路改造的总体设计和桥梁设计要点。对于现状快速路,为提高主线的连续性和独立性,总体方案宜将现状地面段改造为高架段,同步将现状枢纽型“低接高”立交改造为“高接高”立交,使主线系统和地面辅道系统的影响降到最低;在一些重要主干路口,结合主线改造,通过增设平行上/下桥匝道形成简易菱形立交,实现主线高架与辅道到发交通的快速联系;从总体方案考虑,增设声屏障;从对交通影响最小考虑,主线桥梁上部结构宜采用钢-混组合梁。帮宽桥根据地面绿化带布置,下部结构采用分离式柱式墩和带牛腿的偏心柱式墩,上部结构宜采用钢箱梁,帮宽桥与既有桥之间设置0.02 m的沉降缝。设计经验的总结为同类型设计提供了参考和借鉴。

Taking the reconstruction project design of Baishazhou Avenue as an example, the general design & bridge design points of expressway reconstruction are proposed. For the existing expressway, in order to improve the continuity & independence of the main line, the overall plan should transform the existing ground section into an elevated section, and simultaneously transform the existing hub type low to high interchange into high to high interchange, so as to minimize the impact of the main line system and the ground auxiliary road system. At some important trunk intersections, combined with the reconstruction of the main line, a simple diamond-shaped interchange is formed by adding parallel up/down bridge ramps to realize the rapid connection between the main line viaduct and the auxiliary road arrival & departure traffic.Considering the overall plan, sound barrier is added;considering the minimum impact on traffic, the superstructure of the main line bridge should adopt steel-concrete composite beams. The widening current bridge is arranged according to the ground green belt. The lower structure adopts separated column piers and eccentric column piers with corbels. The upper structure should adopt steel box girder. A settlement joint of 0.02 m is set between the widening current bridge & the existing bridge. The summary of design experience provides reference for the same type of design.