Frazil ice jam risk assessment method for water transfer projects based on design scheme

Abstract

Abstract Frazil ice jam risk assessment is an important method to improve the operational safety of water transfer projects. A frazil ice jam assessment method was developed based on project design conditions to ensure the risk level of frazil ice jam. A frazil ice jam risk assessment indicator system was incorporated into the method that included three first-level indicators, such as ice production, special hydraulic structure and basic design parameters, and 17 third-level indicators for calculation analysis. Then, a standard assessment system was proposed, and an analytic hierarchy process method was used to determine the magnitude of the frazil ice jam risk. Finally, the method was used to study the Middle Route of the South-to-North Water Diversion Project (MRSNWDP) from the Guyunhe to Beijumahe canals. The results showed that all of the canal pools had frazil ice jam risk levels between III and IV, of which approximately 15% of the pools have risk level IV, and the canal pools with risk level IV were reported to have ice jam incidents, and it suggested that the ice condition prediction, engineering operation process in winter, engineering measures for disaster reduction and emergency plan refinement need to be strengthened for the pools with risk level IV. Therefore, the method of frazil ice jam risk assessment based on project design conditions can perform well in both the built-operating stage and the design stage of water transfer projects. Frazil ice jam risk prevention is a task through the full life-cycle of water project construction, it is necessary to do risk assessment work at design stage, and the work should be written into the national standard.