泥沙研究

宿连航道是江苏省干线航道网重要组成，规划等级为二级，在宿迁境内长距离横穿新沂河，新沂河泄洪时下泄水流跨越规划航槽形成强劲横流，制约通航历时和通航安全。在现场水文测验和地形测量基础上，建立了平面比尺1:200、垂直比尺1:80的整体物理模型，针对交汇区水流难以扩散的难题，在最大通航流量2 710 m³/s条件下，以航道内横向流速小于0.5 m/s为整治目标，研究提出扩挖疏浚为主，辅以航槽加宽、改扩建闸、引导流等多组合措施，经比选扩挖角25°时分散水流降低横流效果最优，进而形成综合整治方案，选择合适的模型沙，开展了泥沙淤积试验，结果表明推荐方案实施后，经历典型年水沙过程作用，水流快速横穿扩挖区，航槽内泥沙回淤幅度较轻，不利年份经适量疏浚即可维持整治效果和船舶航行水深。

The Suqian-Lianyungang Waterway, a vital component of Jiangsu Province′s trunk waterway network which is planned as Class II, traverses the Xinyi River over a long distance. During flood seasons, concentrated crossflows in the Xinyi River over the planned navigation channel create strong transverse currents, significantly restricting navigation duration and safety. Based on field hydrological and topographic measurements, a comprehensive physical model was established with plane scale 1:200 and vertical scale 1:80. To address the challenging flow dispersion at the confluence zone under maximum navigable discharge condition(2 710 m³/s), with the target of maintaining transverse velocities below 0.5 m/s within the channel, the regulation measures of expansion dredging, channel widening, sluice gate expansion and flow guidance were proposed. After comparative analysis, a 25° expansion angle was proven to be optimal for flow dispersion and reduction of transverse current, thus forming the comprehensive regulation scheme. Using properly scaled sediment, sedimentation tests demonstrated that water rapidly crosses the expanded zone and navigation channel experiences minimal sediment redeposition under typical annual flow-sediment conditions. During hydrologically unfavorable years, targeted maintenance dredging can adequately preserve both the regulation effectiveness and requisite navigation depths.