城市设计暴雨频率计算问题

The Problems of Frequency Compunction on the Urban Design Storm

城市设计暴雨，具有历时短、设计标准较低的特点，与常用的频率计算方法不尽相同。简述了暴雨系列的取样问题；改正了与经验频率有关的计算公式；提出以经验适线法来拟合暴雨系列是反Ｓ形的分布；比较了推求设计暴雨的几种方法，认为超定量综合法有偏于安全的结果；列述了我国一些城市的暴雨强度公式，其中的参数无一定的规律性，期望进一步工作，在点面上进行协调。

For urban design storm, there are some features which are shorter duration and lower design level. It differs from commonly used method of frequency computation. In this paper, the calculated formula related to empirical frequency are corrected, inverse S-shape distribution to fit the storm series by empirical curve-fitting technique is suggested, and the results which is on safe side by using the excess a specific-value method are recognized.ln addition, the storm intensity formula of some city in China are listed. There is no certain rule to its parameters. It is hoped that further study is needed to harmonize the parameters from single to areal sites.