山区河道型水库弯曲段滑坡涌浪特性及对航道通航影响机理的研究

Water waves generated by landslides frequently occur in mountain channel type reservoirs. Navigation safety is serious threatened. Affected by the curve shape and the structure of the three-dimensional fluid, characteristics of water waves generated by landslides at the reservoir bending reaches and its influence on navigation mechanism are more complicated. Based on the preliminary studies, this project is mainly to study the characteristics of water waves generated by landslides and the influence to the channel at curved reaches of mountain river-type reservoirs. The project selects water waves generated by landslides in the three gorges reservoir as the main research object, on the basis of fluid mechanics, wave theory and curved channel dynamics, through generalized model experiment in the flume, theoretical analysis and computational simulation research, to explore the reservoir the basic characteristics of the water waves generated by landslides and the change rule of each factor at the reservoir bending reaches; to put forward the calculation methods about ship's mooring force and impact force and impact of mooring ships to dock under the action of water waves generated by landslides; to reveal ship rolling characteristics and the changing rule of the mooring ship anchor chain under the action of water waves generated by landslides; to propose method to confirm the range of safe navigation of the ship under the influence of water waves generated by landslides; to establish the three dimensional mathematical model of water waves generated by landslides at reservoir bending reaches; to build techniques system used to evaluate the degree of impact on the navigation condition. The research results can provide theoretical and technical support to effectively prevent or reduce the disasters loss caused by landslide surge in harbor engineering and sailing ship safety, in addition, enrich the contents of water dynamics and port and waterway engineering discipline.

山区河道型水库滑坡涌浪灾害频繁发生，航道通航安全受到严重威胁。受弯曲河道形态和三维流体结构的影响，在水库弯曲段滑坡形成的涌浪特性及其对航道通航的影响机理更为复杂。本项目拟在前期相关研究的基础上，着重研究山区河道型水库弯曲段滑坡涌浪特性及对航道通航的影响机理。以流体力学、波浪理论及弯曲河道动力学为基础，通过模型实验、理论分析和数值模拟研究，探索水库弯曲段滑坡涌浪的基本特征和各要素的变化规律；提出滑坡涌浪作用下船舶系缆力、系泊船舶对码头的撞击力和撞击能的计算方法；揭示滑坡涌浪作用下船舶横摇特征及锚泊船舶锚链拉力的变化规律；提出滑坡涌浪影响下船舶安全航行范围的确定方法；构建水库弯曲段滑坡涌浪的三维数学模型及滑坡涌浪对通航安全影响程度的评价信息系统。研究成果可为有效地预防或减少滑坡涌浪对港口航道工程和船舶安全航行所造成的灾害损失提供理论和技术支持，并丰富水动力学和港航工程等学科内容。

山区河道型水库形状蜿蜒狭长，较大方量岩土体入水后会造成局部地形发生剧烈变化，引起河道堵塞，并产生巨大涌浪，严重影响库区航道通航安全。受河道形态影响，在水库弯曲段产生的涌浪特性及对航道通航影响机理较顺直段更为复杂。本项目通过三维物理模型实验、理论分析和数值模拟等研究手段，对弯曲河道型水库背景下的滑坡涌浪近场波特性、涌浪沿程传播衰减规律、涌浪作用下系泊船舶对码头的撞击力、涌浪对船舶摇摆性及锚泊船舶锚链拉力、涌浪对库岸冲刷特性、涌浪影响下船舶安全航行范围计算方法等内容进行了系统且深入地研究。研究取得以下重要结果：. （1）建立了初始涌浪波幅、波高、波长、周期、波速计算公式，并分析了初始涌浪沿直道与弯道的传播衰减规律。. （2）建立了滑坡体对岸涌浪最大爬高的理论计算公式，并揭示了涌浪爬高沿顺直河岸与弯曲河岸的变化规律。. （3）分析了滑坡涌浪作用下类土质岸坡的冲刷特性，建立了不同岩土体岸坡的最大冲刷深度经验公式。. （4）揭示了涌浪作用下系泊船舶对高桩码头撞击力的变化规律、码头桩基与面板上波压力的分布规律以及对锚泊船舶锚链拉力的影响规律，给出了涌浪作用下高桩码头桩上最大动水压强的计算公式以及面板底部冲击压强的计算公式。. （5）构建了以山体滑坡变形破坏阶段、涌浪规模、涌浪损毁船舶的系统风险综合系数为测度指标的海事风险评判模型。. （6）提出了涌浪作用下的船舶通航安全极限浪高及影响范围，基于ArcGIS Engine等软件平台，建立了滑坡涌浪对航道通航安全评估技术信息系统。. （7）采用VOF法追踪自由液面模拟涌浪产生及传播过程，建立了适用于水库弯曲段的滑坡涌浪数值模型。. 本项目取得的研究成果应用于三峡库区和长江上游航道维护和船舶安全航行管理之中，可为有效地预防或减少库岸滑坡涌浪对港航工程和通航船舶造成的灾害损失提供理论与技术支持，丰富了水库区滑坡涌浪灾害风险评估及航道通航安全等学科内容。