常泰长江大桥桥跨布置方案研究

Study of Span Arrangement Options for Changtai Changjiang River Bridge

为确定常泰长江大桥合理的桥跨布置方案,对桥位处的河床演变进行分析与预测,综合考虑工程河段河道条件、航道条件及通航环境等因素,分析论证大桥的通航孔布置及墩位布设方案。经分析论证,最终桥位跨长江主航道采用主跨1176m、边跨490m的桥型方案;天星洲左汊及录安洲右汊采用主跨388m、边跨168m的桥型方案。所采用的方案通航孔均基本覆盖了历年航道变化及通航水域范围,对12.5m深水航道及专用航道布置,以及对船舶通航、相邻码头运行、岸坡及天星洲尾部低滩稳定的影响均相对较小;且失控船舶碰撞桥墩的概率较小,危险程度较低。

Based on the analysis and prediction of the riverbed evolution at the bridge site,different navigable span arrangement and pier distribution solutions were analyzed and verified for Changtai Changjiang River Bridge,taking into account the related factors,such as watercourse condition,navigation channel condition and the navigation environment.According to the results of the analysis and verification,the main navigational channel bridge of Changtai Changjiang River Bridge is designed as a cable-stayed bridge with a main span of 1176mand two side spans of 490 m,while the left branch(Tianxing Islet side)and right branch(Lu′an Islet side)are arch bridges with main spans of 388mand side spans of 168m.The navigable spans in the final design are all capable of crossing the regions exhibiting navigation channel change over years and the navigable waters,aiming to reduce the influence of bridge on the distribution of 12.5m-deep navigation channel and special navigation channel as well as the normal service of adjacent harbors,bank slopes and stability of lower shoal at the tail of Tianxing Islet to the minimum.In addition,the probability of ship-bridge collision is low,thereby the potential risks are reduced.