重庆市主城区设计暴雨量推算探讨

The Calculated Design Rainstorm in the Central Districts of Chongqing

设计暴雨量是城市勘查设计重要标准之一.根据年最大值法与年多个样法选取的重庆市主城区沙坪坝站1961-2013年60,120,180,360,540,720,1 440min历时资料,采用皮尔逊Ⅲ型分布、耿贝尔分布、指数分布、对数正态分布、广义帕雷托(GP)分布函数对其进行拟合,并对拟合效果进行检验,结果表明:GP分布函数的拟合效果最好,可信度更高.重庆主城区推荐使用GP分布函数拟合的设计暴雨量.当所需设计暴雨量的各历时及其资料年限与暴雨强度公式编制时使用的相同时,可用暴雨强度公式计算设计暴雨量,否则会有误差.

The design rainstorm is one of the important urban design standards. Based on the different du- ration rainfall such as 60, 120, 180, 360, 540, 720 and 1 440 rain, diachronic data at the Shapinba Weath- er Station in the central districts of Chongqing was selected by the annual maximum value method and the annual multi-sampling method from 1961 to 2013, and was fitted with the Pearson HI distribution, the Gumbell distribution, the exponential distribution, the logarithmic normal distribution and the GP distri- bution, respectively. The fittings were then tested. The fitting of the GP distribution gave the best results and the highest reliability. So, the design rainstorm of the central districts of Chongqing fitted with the GP distribution is recommended. When the duration rainfall and data period for calculating the design rainstorm are the same as for organizing rainstorm intensity formula, the rainstorm intensity formula should be used to calculate the design rainstorm; otherwise, errors may occur.