水流输入对大比降入湖三角洲演化的影响评估试验  

Evaluation experiment of the impact of water inflow on the evolution of a lacustrine delta with large terrain gradient

作　　者：宋晓龙[1,2] 徐海珏[1,2] 白玉川[1,2] SONG Xiao-long;XU Hai-jue;BAI Yu-chuan(State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation,Tianjin University,Tianjin 300350,China;Institute for Sedimentation on River and Coastal Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学水利工程智能建设与运维全国重点实验室,天津300350 [2]天津大学河流海岸工程泥沙研究所,天津300350

出　　处：《泥沙研究》2024年第4期6-12,41,共8页Journal of Sediment Research

基　　金：国家自然科学基金项目(51879182);天津市科技计划项目(21JCQNJC00480)。

摘　　要：三角洲是河流携带泥沙入湖或入海时泥沙沉积形成的一种河口地貌。当三角洲上游地势相对较高、整体纵比降较大时,局部沉积体具有冲积扇的特性,三角洲演化过程表现出复杂系统的不确定性。通过进行重复自然模型试验,评估了两种不同流量水流输入对大比降三角洲沉积体形成演化的影响。基于三角洲沉积体横断面结构的多峰高斯函数拟合及其特征参数时变波动性的统计分析,结果表明,在小流量条件下三角洲上游堆积体具有多方向发展的不确定性,在大流量条件下堆积体具有纵向多层级结构化发展的不确定性特征。Delta is a type of estuarine landform formed by sediment deposition when rivers carry sediment into lakes or seas.When the upper delta is at a higher elevation and has a relatively steep longitudinal slope,the sedimentation will locally exhibit significant alluvial fan features.The formation and evolution of the entire delta demonstrates the uncertainties of the complex system.By conducting repeated natural modeling experiments,the impact of two different water inflow rates on the formation and evolution of sedimentation in a lacustrine delta with steep terrain gradient has been evaluated.Based on multi-peak Gaussian fitting of cross-sectional sedimentary characteristics and statistical analysis of temporal fluctuations of its characteristic parameters,it is shown that the development of upstream delta under low flow conditions exhibits multi-directional uncertainties,while the accumulation under high flow conditions exhibits vertical multi-level structured uncertainties.

关 键 词：水流输入 大比降入湖三角洲 冲积扇特性 堆积结构不确定性 

分 类 号：TV148.3[水利工程—水力学及河流动力学]