基于冲积系统趋衡响应模型的河床冲刷研究与预测  

Study on the riverbed erosion and prediction based on equilibrium response model in fluvial channels

作　　者：景唤 张红武[3] 王彦君 王永强[1,2] 钟德钰 JING Huan;ZHANG Hongwu;WANG Yanjun;WANG Yongqiang;ZHONG Deyu(Changjiang River Scientific Research Institute,Hubei Key Laboratory of Water Resources&Eco-Environmental Sciences,Wuhan 430010,China;Research Center on the Yangtze River Economic Belt Protection and Development Strategy,CWRC,Wuhan 430014,China;State Key Laboratory of Hydroscience&Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]长江水利委员会长江科学院水资源与生态环境湖北省重点实验室,湖北武汉430010 [2]长江水利委员会长江经济带保护与发展战略研究中心,湖北武汉430014 [3]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水利学报》2022年第11期1350-1360,共11页Journal of Hydraulic Engineering

基　　金：复杂调水工程全生命周期风险分析与管控关键技术(HNYJJH JS FWKY 2021004);国家重点研发计划项目(2016YFC0402500);中央级公益性科研院所基本科研业务费项目(CKSF2021486);国家自然科学基金项目(52009145)。

摘　　要：运用河流辩证法原理分析非平衡态河流的演变趋势,可见水沙或边界变化等扰动引发的系统偏差普遍表现出时空衰减的特性,在趋于新平衡态的过程中,水流与河床的相互作用总是使偏差朝减小的方向调整,遵循“趋衡性”或“趋衡响应原理”。据此假定扰动发生概率符合泊松分布及单个扰动响应强度满足指数衰减率,给出冲击系统趋衡响应模型的初步形式,基于美国多座水库下游河道实测数据的规律性检验表明,冲积系统对扰动的响应强度随时空推移呈非线性衰减趋势,体现了河流演变的时空趋衡性。在此基础上,选取泥沙起动难度与水流强度反映影响床面泥沙运动状态的两个矛盾方面,以两者之比作为定量描述趋衡衰减系数的动力学参量,率定相关系数后模型即有定量预测水库下游河道河床累计冲刷深度的功能。进而,运用基于三门峡水库下游实测资料率定后的模型对黄河中游古贤水库修建后下游河道的沿程冲刷及潼关高程下降引起的渭河下游河道溯源冲刷过程进行预测。结果表明,龙门和潼关的计算河床累计冲刷深度分别为1.84 m和1.43 m;潼关高程下降引起的渭河下游溯源冲刷河段长度约为250 km,华县、渭南溯源冲刷深度分别为0.54 m和0.25 m。研究成果为冲积河流非平衡态时空调整过程的预测提供了新思路,具有较大工程应用价值。The principle of river dialectics is used to analyze the temporal and spatial evolution trend of nonequilibrium fluvial rivers.It is found that the deviation of fluvial system caused by disturbances such as changes in water,sediment or boundary conditions generally exhibits the characteristics of temporal and spatial attenuation.In the process of approaching the new equilibrium state,the interaction between the flow and the riverbed always causes the deviation to be adjusted in the direction of decreasing,following the“equilibrium characteristics”or“equilibrium response principle”.On the basis,through assuming the disturbance probability conforms to Poisson distribution and the response intensity of individual disturbance satisfies exponential decay law over time,this paper gives a preliminary equilibrium response model.The regularity test of the model using collected geometry observations in channels downstream of dams in the United States shows that the response intensity of the fluvial river to disturbance declines nonlinearly over time and space,reflecting the temporal and spatial equilibrium trend of river evolution.In the deepening research stage,the difficulty of sediment initiation and the flow intensity are selected to reflect the two contradictory roles that affect the sediment movement state on the riverbed,and the ratio of the two is used as a river dynamic parameter to quantitatively describe the equilibrium decay coefficient.Following the related parameters are calibrated,the model has the function of quantitatively simulating the cumulative riverbed degradation downstream of the reservoir.Then,the calibrated model based on the measured data in the lower reaches of Sanmenxia Reservoir is used to predict the streamwise erosion following the construction of Guxian Reservoir in the middle Yellow River and the backward erosion caused by the degradation of Tongguan elevation in the lower Weihe River.The results show that the cumulative riverbed degradation at Longmen and Tongguan is 1.84 m and 1.

关 键 词：冲积系统 趋衡响应模型 黄河 时空调整 沿程冲刷 溯源冲刷 古贤水库 

分 类 号：TV143[水利工程—水力学及河流动力学]