泥沙粒径组成的不均匀性对海岸地形演变的影响  

Effect of heterogeneous sediments on beach topography evolution

作　　者：徐杰 邹志利[1] XU Jie;ZOU Zhi-li(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《海洋通报》2018年第4期440-449,共10页Marine Science Bulletin

基　　金：国家自然科学基金(50879006);国家创新群体基金(KZCX2-YW-JS305)

摘　　要：海岸的泥沙输沙模式决定着海岸地形的演变特征,不同的输沙模式会导致形成横向和倾斜沙坝、裂流沟槽等不同的地貌特征。本研究提出了一种考虑泥沙分布不均匀性的新输沙率公式,该公式包含了反映泥沙粒径不均匀性的概率加权和考虑泥沙颗粒遮蔽效应的加权。该公式所给出的载沙量与传统输沙率公式的对比表明,相同中值粒径下,二者有明显差异。将该输沙率公式应用于地形线性不稳定分析,所得到的地形不稳定性增长率不同于假定泥沙为均匀的结果,对应的地形变形波长也有所差别。The morphological evolution of coastal topography depends on the coastal sediment transport model, and different transport modes can lead to the formation of different topography characteristics, such as transverse and oblique bar, rip channel system and so on. This study proposes a new sediment transport formula which takes the heterogeneousness of sediments into account, which considers both the weightings of sand distribution probability and sand hiding effects. The result of comparing the sediment transport rate with traditional sediment transport rate shows that it has obvious difference for the cases of same mean sand size. When the transport rate formula is used in the topography linear stability analysis, it shows that the topography instability growth rate will be different from the result with uniform sediment assumption, and the corresponding spatial topography form and wavelength also show some difference.

关 键 词：地形线性不稳定分析 泥沙粒径 输沙率 海岸形态 

分 类 号：TV148[水利工程—水力学及河流动力学] TV142