南通港吕四港区进港航道试挖工程回淤监测研究

Observation on siltation in Lvsi trial dredged channel in Nantong port

南通港吕四港区进港航道地处苏北辐射沙洲南缘，为自然水深航道，缺少航道开挖的工程实践。吕四进港航道扩建阶段在小庙洪水道开展了航道试挖工程，并进行了为期1a的回淤监测。研究表明，正常天气情况下试挖槽年回淤强度为0．74m／a，回淤强度不大；一次常年大风过程平均淤积厚度基本不超过0．1m，正常年份的大风过程对回淤的影响有限；在遭遇了当地5～10a一遇的“梅花”强台风作用下的淤积厚度约0．28m，未出现明显“骤淤”现象。上述研究成果为吕四进港航道的扩建提供了技术支撑，也为辐射沙洲海域航道回淤研究提供重要的科学参考。

Lvsi approach channel is located in south margin of Subei radiation shoals. The approaching channels are all natural depth at radial sand ridges in North Jiangsu. In order to provide a scientific basis for the expansion of the Lvsi approach waterway, we carried out the trial dredged channel in Xiaomiaohong waterway. The siltation observation includes the topographic survey, hydrologic survey, bottom sampling, etc. The result indicates that the siltation of trial dredged channel is week in the normal condition, the influence of a normal year wind process on the siltation is limited, the significant sudden siltation does not happen after Typhoon Muifa with 5 to 10 year frequencies.