Risk Analysis Of Earth-Rock Dam During Construction Period In Flood Season And The Multi-Objective Decision For Construction Diversion Scheme

The construction period of earth-rock dam is the high incidence period of overtopping dam break.The construction diversion risk analysis is necessary while the engineering is planned and designed.The decision of construction diversion scheme is one of the key points of earth-rock dam during the construction period,and the design scheme needs to coordinate the indexes of diversion project cost,construction period and potential loss,which is influenced by each other.Therefore,the multi-objective decision of diversion scheme is of great theoretical and practical significance.This study analyzes the risk of earth-rock dam during construction period in flood season,and the TOPSIS method is introduced to construct the multi-objective decision-making model of diversion scheme.The main research work and results are as follows:(1)Risk analysis of earth-rock dam during construction period in flood season.This study analyses the uncertainty of key factors such as reservoir inflow flood processes,discharge capacity of diversion structure and flood prevention height of earth-rock dam during interim flooding.Monte-Carlo method is used to simulate the uncertain factors and risk assessment model of earth-rock dam during construction period is established to calculate the risk in flood season,which provide basis for risk control of flood control.(2)Multi-objective decision of diversion scheme during construction period of earth-rock dam.Choosing the determinate investment cost of diversion building,the risk loss of diversion system’s failure and the average construction intensity of diversion building as the main indicators of multi-objective decision,and the weight of each decision indicator is calculated by the improved analytic hierarchy process and the improved entropy weight method from subjective and objective aspects.The TOPSIS method is used to optimize the optimal diversion scheme under each weight combination,and a multi-objective decision-making model of diversion scheme in construction period of earth rock dam is established,which can provide intuitive and effective tool for optimal diversion scheme decision.(3)Example application.The risk analysis model and the multi-objective decision model for diversion scheme constructed in this paper is applied to the comparison of diversion scheme in the construction period of Qianping Reservoir in Henan Province.The decision results provide effective guidance for the formulation of diversion scheme of the project,and testifies the scientific significance and the practical value of the model constructed in this paper.