漫坝风险分析在水库防洪中的应用

Application of Overtopping Risk Analysis for the Earth Dams of Flood-control Reservoirs

综合应用随机水文学、随机水力学等学科知识,全面考虑洪水、风浪、库容和泄水能力的不确定性,建立了土坝对抗洪水和风浪联合作用下的漫坝风险理论,并提出了风险取值标准。此法是防洪减灾的一种辅助策略,可在坝体坚固、管理人员素质较高的大型水库推广应用。

It should be ensured that the dam is safe during flood period. Among the dam failures both domestic and overseas, the failures of earth dam are in the majority, whereas the majority of earth dam failures are initiated from overtopping and thereby dam break. The research on applying overtopping risk analysis technique to the safe evaluation against overtopping and increasing the benefits of flood-control reservoirs is described in this paper. Considering thoroughly the uncertainties of flood, wind, reservoir storage and discharge capacity, the authors developed the theory of overtopping risk against the design series of flood and wind simultaneously. A risk criterion or an acceptable risk of overtopping was also recommendated by the authors. In the paper, particular emphasis will be paid on the applications of the overtopping risk theory to Duohe Reservoir, Qinghe Reservoir, Yuecheng Reservoir and Zhuzhuang Reservoir as well as the increasing of their economic benefits as the meanwhile the dams are safe during flood with their reliability against overtopping of 99.999% or more. Wide spread of the technique of overtopping risk analysis will bring us remarkable economic and social benefits. As a non-structural measure, the technique of overtopping risk analysis applied to large reservoirs with strong dams and high quality staffs may be considered as an auxiliary strategy on reservoir flood-control and damage reduction.