感潮河段洪潮遭遇组合风险研究

Risk Probability Study on the Combination of Flood and Tide for Tide-affected River

洪潮遭遇分析和洪潮组合的合理选取是感潮河段整治规划设计中的重要内容。构建的洪潮遭遇组合的风险分析模型,首先采用Copu la函数构建感潮河段的年最大洪水流量和相应潮位的联合分布以及年最高潮位和相应洪水流量的联合分布,再基于联合分布提出遭遇组合的风险分析模型。并以漠阳江河口段的洪潮遭遇组合分析为实例来研究。结果表明,①以洪为主,50年一遇的设计洪水与下游多年平均潮位相组合的风险率为6.89%,②以潮为主,50年一遇的设计潮位与其上游多年平均洪水相组合的风险率为4.77%。根据洪潮遭遇组合风险模型来确定遭遇组合,可为感潮河段洪潮遭遇组合的合理选取提供科学依据。

The analysis of floods meeting with tides and the rational selection of the combination of floods and tides are vitally important in planning design for the tide affected rivers. The model for the risk probability of the combination of floods and tides was established in this paper. Firstly, the different copula functions were used to build the bivariate joint distribution of annual maximum flood discharge and its corresponding tidal level and the annual maximum tide level and its corresponding flood discharge, respectively. Then, based on both mentioned above the risk probability analysis models for the combination of floods and tides were put forward. The case study of the combined risk probability of floods and tides for the estuary of the Moyang River was conducted. The results indicated ： （ 1 ） The combinatorial risk proba- bility of the design flood discharge with the fifty-year return period and the average value of annual maxi- mum tide level was 6. 89% ; （2） The combinatorial risk probability of the design tide level with the fiftyyear return period and the average value of annual maximum flood discharge was 4. 77%. The models for combined probability of the floods and the tides can be used to measure the risk probability of the combination of floods and tides, which can provide scientific basis for the rational selections for the combinedprobability of floods and tides.