Comprehensive Evaluation And Threshold Research On Reservoir Flood Control Operation Risk

Water is a necessary natural resource for human survival and development,and it is also a material guarantee for maintaining the sustainable development of the social economy.Due to the limited availability of water resources in China and the frequent occurrence of floods and floods,the shortage of water resources has seriously restricted China's economic development and social stability.In response to these problems,the state has attached great importance to research on water resources development and utilization in the 21 st century.The initial concept of flood resource utilization is a new way to solve the problem of water shortage,and it has become one of the effective measures to improve water resource utilization.The reservoir is an important water conservancy project for flood control and benefit.Through comprehensive assessment of the flood prevention risk of the reservoir and the whole downstream,selecting the appropriate flood season water level under the premise of ensuring acceptable risks can effectively improve water resource utilization.The comprehensive assessment of reservoir flood control risk assessment provides important technical support.The main research contents and results of this paper are as follows:(1)Comprehensive assessment of reservoir flood control risk by combined weighting method.The risk estimation of reservoir flood control scheduling is mainly composed of risk factor identification,risk factor simulation and reservoir flood control simulation calculation.By identifying the main risk factors of reservoir flood control dispatching process,the design flood process,flood forecast error,reservoir scheduling delay,Five risk factors: water level-reservoir relationship and reservoir discharge error.The Monte Carlo method is used to simulate the different design flood processes considering various risk factors.The reservoir flood control simulation model is used to complete the risk estimation.According to the above method,the risk is selected.The Spearman rank correlation coefficient determines the sensitivity of each risk factor in the reservoir scheduling process.Then,by analyzing the possible risks of the various risk areas of the reservoir,according to the expert opinions,a number of risk indicators are scientifically screened,and a comprehensive evaluation index system for reservoir flood control dispatching risk is established,including reservoir risk,reservoir area risk and downstream risk.The weight of each risk indicator is determined by the combination weighting method,and then the reservoir dispatching risk is comprehensively evaluated.(2)The fuzzy clustering iterative model optimized by chaotic differential evolution algorithm(CDE algorithm)is used to formulate the risk threshold of reservoir flood control.According to the above methods of risk estimation and comprehensive evaluation,the risk comprehensive assessment of different design frequency flood processes is carried out,and the risk indicators are divided into several risk levels.The fuzzy clustering iterative model program loop iterative operation under the optimization of CDE algorithm makes the sample space Each sample is gathered around each risk level,and the values of the different levels of the risk indicators are obtained.The risk threshold of the reservoir flood control is determined according to the weight of the indicators.(3)A comprehensive risk assessment of the Luyu Reservoir was carried out using the above method model.Firstly,by analyzing the historical flood data of Lujing Reservoir for many years,the typical flood processes in the front and back flood seasons are separately scaled up to estimate the different design flood processes considering various risk factors.Secondly,the flood control dispatch risk comprehensive evaluation of Luyu Reservoir is carried out.According to the combination weighting method,the risk comprehensive value of each water level scheme is determined.Finally,the risk comprehensive evaluation result is used to formulate the risk threshold of the Luyu Reservoir flood control dispatching process by using the CDE-fuzzy clustering iterative model,and the risk level of each water level scheme is determined by comparing the risk thresholds.Preferably,the optimal water level scheme is selected,and the analysis result is recommended to be recommended,and relevant countermeasures for reducing risks are proposed.