北江清远枢纽三线船闸通航水流条件及优化措施

Navigation flow conditions of third-line ship lock of Qingyuan Hub in the Beijiang River and optimization measures

北江水运需求增长、航道扩能升级,拟在清远枢纽一、二线船闸基础上新建三线船闸并预留四线船闸建设空间。针对三线船闸左岸建设方案建立平面二维水流数学模型,研究引航道口门区及连接段通航水流条件及存在的问题。结果表明:1)在工况2~4(Q≥5 000 m^(3)/s),三线船闸上游口门区横流显著,大于0.3 m/s。2)船闸下游大燕河水流入汇直冲航道。工况3中大燕河流量为1 510 m^(3)/s时,汇口处连接段横流超标、通航条件差。3)进一步对船闸方案进行优化试验后,采取上游口门区增设导流墩、下游大燕河口布置导流顺坝和导流墩、拓宽浚深大燕河口的措施,可有效改善横流。

With the increasing demand for water transport in the Beijiang River and the expansion and upgrading of the waterway,it is planned to build a new third-line ship lock on the basis of the first-line and second-line ship locks of the Qingyuan Hub,and reserve space for the construction of fourth-line ship lock.Based on the construction scheme of the left bank of the third-line ship lock,a plane two-dimensional water flow mathematical model is established to study the navigable flow conditions and existing problems in the entrance area of the approach channel and the connecting section.The results show that:1)In working conditions 2 to 4(Q≥5 000 m^(3)/s),the cross flow in the upstream gate area of the third-line ship lock is significant,which is greater than 0.3 m/s.2)The flow of the Dayan River in the lower reaches of the ship lock flows into the straight channel.In working condition 3,when the flow rate of the Dayan River is 1 510 m^(3)/s,the cross flow of the connecting section at the confluence exceeds the standard and the navigation conditions are poor.3) After further optimization test of the ship lock scheme,measures such as adding diversion piers in the upstream mouth area,arranging diversion dams and diversion piers in the downstream Dayan River mouth,and widening the dredged Dayan River mouth can effectively improve the cross flow.