岷江朱石滩航道整治工程方案计算与分析

Calculation and analysis of channel improvement scheme in Zhushitan reservoir area of Minjiang river

朱石滩下游1.4 km拟建的岷江二桥其215 m主通航孔位于航道右侧,与新槽的衔接存在较大问题;目前老槽水深不足,不能通行大件运输船舶。首先建立平面二维水流泥沙数学模型,并由实测资料验证其相似性。数学模型计算的水面线、流速分布及河床冲淤等与原型实测资料基本吻合,验证精度符合规范的要求。在掌握河床演变、滩险成因和碍航情况的基础上对老槽、新槽方案进行比较分析,提出达到Ⅳ级航道标准,满足大件运输需要。结果表明:该数学模型可较好地模拟河段水流的运动及航槽泥沙的淤积过程,从整治效果看(通航水流条件、航槽稳定等),3个方案各有优劣,相对而言,老槽方案较好,更能满足航道通航条件要求。

The second Minjiang river bridge to be built locates 1.4 km downstream of Zhushitan, the 215 m-long main navigable hole of which locates on the right side of the channel, and the linking of which to the new groove faces a big problem. At present, the old groove is not deep enough for the passing of large transport ships. The 2-D flow sediment mathematical model is established, and the similarity is verified by the measured data. The calculating results of the water line, the velocity distribution and the river bed scour are consistent with the measured data, so the accuracy meets the specification requirements. To reach the IV channel standard and meet the need of large transport ships, we compare the schemes of old groove and new groove. The results show that the mathematical model can simulate the movement of the river flow and sediment deposition process of navigation channel. It shows that three schemes all have their own advantages and disadvantages from the regulation effect （the flow condition for navigation, navigation channel stability, etc. ）. Relatively speaking, the old groove scheme is better, since it can meet the requirements of the channel＇s navigation condition.