淮河入汇对口岸直水道深水航道整治效果影响的数值计算

Numerical calculation and influence of inflow from Huaihe river on deepwater channel regulation effect of Kou'anzhi waterway

口岸直水道是长江南京以下12.5 m深水航道二期工程重点整治河段之一,该水道上段为多分汊河型,下段为长顺直型,且上段又处于弯道和淮河入汇,河段内滩槽变化剧烈,航道条件影响因素复杂,其中,淮河大流量入汇是落成洲浅滩形成的重要原因。采用数学模型手段计算分析淮河入汇对口岸直水道深水航道整治效果的影响。计算表明:淮河大流量入汇,使淮河入江口以上三益桥边滩、左汊12.5 m设计航槽内淤积幅度和范围均有所增加,受其影响,落成洲左汊设计航槽内不满足12.5 m等深线的最小宽度较不考虑淮河入汇时有所增加,高港边滩设计航槽内浅区不满足12.5 m水深的航道宽度略有减小,鳗鱼沙右槽下段12.5 m设计航槽内不满足12.5 m水深的航道宽度较无淮河影响时略有增加。

The Kou＇anzhi waterway is an important part in the second phase of the regulation project of 12. 5 m deep water channel from Nanjing to the mouth in the Yangtze River. The upper part belongs to braided rivers of many branches,and the lower part is straight rivers. Moreover,the upper part locates in the curved channels,into which Huaihe river flows, the flood-plain changes violently, and the channel conditions are affected by many complicated factors. The large inflow of Huaihe river is the important formation cause for the Luochengzhou shoal.Using the numerical models, we investigate the effects of the Huaihe river inflow on the deep water channel in Kou＇anzhi waterway. The simulated results show that the inflow of Huaihe river causes the amplitude and range of deposition in the Sanyiqiao beach above the estuary of Huaihe river and in the designed navigation channels of12. 5 m at the left branch increasing. Under these influences,the minimum width of the isobath below 12. 5 m in the designed navigation channels at the left branch of Luochengzhou is mildly greater than that without regard to the Huaihe river inflow, the channel width in the designed navigation channels, dissatisfying with 12. 5 m of water depth,slightly decreases in the Gaogang beach,while the similar channel width in the lower part of the right channel of Manyusha has a slight increase from that without considering the Huaihe river inflow.