推求暴雨强度公式时的年限选择方法OA

Under the influence of urbanization development,rainfall data in various regions are increasing,and most stations meet the minimum age requirements of urban rainstorm intensity formula,so many stations have data of 40,50 years,or more than 60 years.Therefore,in the actual work of compiling rainstorm intensity formula,how to select the years is of great significance to the derivation of scientific rainstorm intensity formula.Taking Jingdezhen as an example,based on the minute rainfall data from 1961 to 2015,the annual maximum method was used to extract samples.Compare and analyze the appropriate age range from two aspects:sample mean and coefficient of variation.The Gumbel distribution curve is used to fit the samples of three different years,and the parameters are obtained by the least square method.Three rainstorm intensity formulas prepared for different years are obtained and compared.The results show that when compiling the urban rainstorm intensity formula,can choose the age data according to a certain method,count the mean and variation coefficient of all different years,analyze the size and dispersion of the values,according to the local precipitation characteristics,avoid the areas with low mean value and high variation coefficient,confirm the specific range through the percentile method,and comprehensively cross to get the age area.Reasonably handling the relationship between the average size of the sample age and the variation coefficient of the sample age to obtain a scientific preparation age is the basis for the preparation of rainstorm intensity formula,which determines the accuracy and scientificity of the rainstorm intensity formula.