Impact analysis of extreme rainfall treatment on urban waterlogging combating
[Objective]The frequent occurrence of extreme rainfall leads to the emergence of extreme values in rainfall samples,which in turn affects the derivation of the storm intensity formula.In order to study the influence of extreme rainfall samples on the inference accuracy of the storm intensity formula,and to increase its reasonableness in the application of urban flood preven-tion and control,[Methods]taking the rainfall data of Guangzhou in the past 52 years(1969-2020)as an example,based on the 3σ criterion and the yearly substitution of the large value for the large value method,the rainfall samples are determined and processed,and the analysis concludes that the existence of extreme values causes the calculation result of the storm intensity for-mula to be slightly.It was analyzed that the existence of extreme values caused the calculation result of the storm intensity formula to be slightly biased.The flooding model was also constructed using the Hunter Chung drainage sheet as an example,and the difference in the amount of surface inundation between the two method in different rainfall scenarios was analyzed through simula-tion of the Chicago rainfall process line deduced from the storm intensity formulae under different extreme value processing meth-od.[Results]The result show that,compared with the rainfall simulation result derived from the yearly large value method,the surface inundation water volume simulated by the large value method increases by 11.36％～23.70％compared with that of the yearly large value method.[Conclusion]The result show that in practical applications,the use of the yearly large-value method not only ensures the capacity of rainfall samples,but also improves the accuracy of the derivation of the storm intensity formula,which in turn ensures the accuracy of the result of urban flood prevention and control.
万方数据
维普
