Study on Theory and Realization Strategy of Keeping Sequence of Reinforcement Judgment for Existing Levees Based on the Risk Assessment Theory

This paper presents a study on theory and methodology of keeping sequence of reinforcement judgment for existing levee based on the risk assessment theory. On the basis of risk analysis for main failure modes and break losses of levees engineering, an analysis model for reinforcement judgment of the existing levee is presented. The analysis method for risk probability of levee break by all probable breach routs can be discussed, that the relationship between qualitative description for whether or not appearance of failure event and the quantitative failure probability can be analyzed in this analysis method. And assessment model of failure consequences by losses of levee break including population casualties and economic loss and environmental and social influence loss is also studied in this decision-making model, which every loss can be transformed into the loss degree index, then the risk index of different levees can be calculated by product of loss degree index and risk probability of levee break and can be used as the theory foundation for reinforcement judgment of different existing levees.