深水沉井施工对航道条件的影响

针对桥梁建设期间工程河段航道发生不利变化的问题,以沪苏通长江公铁大桥主墩沉井施工为例,对比分析施工前、后的实测水文、地形和航道维护量。结果发现深水沉井吸砂作业和沉井引起的河床冲刷是南通水道近期航道淤积和疏浚维护量大幅度增加的直接原因。因此,应在桥墩结构研究阶段提前考虑施工方案对航道条件的不利影响。

Influence of construction of deepwater caisson on channel condition

In response to the adverse changes in the navigation channel of the project section during the bridge construction,we analyze the measured hydrology,topography,and channel maintenance before and after construction based on the construction of the main pier’s open caisson of Husutong Yangtze River Highway-Railway Bridge. The results show that caissons sand suction operation and riverbed scour are the direct reasons for the recent waterway siltation and substantial increase of maintenance in the Nantong channel. So,the adverse influence of the construction scheme on the channel shall be considered in advance in the early stage of the pier structure study.