【摘要】 面对极端天气频发和洪涝灾害增多的趋势，在小流域洪涝灾害防治方面，确保设计洪水计算的准确性尤为重要，寻求适用于小流域的设计洪水计算方法，能有效提升防洪安全水平。结合兰州地区小流域暴雨洪水特点，采用推理公式法、甘肃省小流域洪峰流量经验公式法、地区暴雨经验公式法和洪峰流量经验公式法，计算典型沟道百年一遇的设计洪水，并分析各类参数的选取方法进而评估其合理性。结果表明：典型沟道洪峰模数之间存在显著的相关性规律，流域面积越大，洪峰模数越小。甘肃省小流域洪峰流量经验公式法的洪峰模数接近各方法平均值，其洪量计算结果较为合理；推理公式法计算结果较为真实，但所需参数较多。两者相比，前者表达式简单、计算方便。在该方法中，选用C_V=2F^-0.08,C_S=3C_V确定洪峰模比系数，得到的设计洪水结果精度最高，符合兰州地区的特点，可为小流域洪水计算方法的选取提供参考。更多还原

【Abstract】 Facing the trend of frequent extreme weather and the increasing flood disasters, it is particularly important to ensure the accuracy of design flood calculations in the context of flood prevention and control in small watersheds. Seeking design flood calculation methods applicable to small watersheds can effectively improve the level of flood safety. Combining the characteristics of small watershed rainstorm floods in Lanzhou area, the rational formula method, the empirical formula method of small watershed flood peak flow in Gansu Province, the regional rainstorm empirical formula method and the empirical formula method of flood peak flow were adopted to calculate the once-in-a-century design flood of typical channels, and the selection methods of various parameters were analyzed to evaluate their rationality. The results show that there is a significant correlation pattern between typical gully flood modulus, with the larger the watershed area, the smaller the flood modulus. The flood peak modulus value of the empirical formula method of flood peak flow in small watersheds in Gansu Province is close to the average value, and the result of its flood volume calculation is relatively more reasonable. The rational formula method calculates more realistic results, but requires more parameters. Compared to the two, the former expression is simple and easy to compute. In this method, the relationship of C_V=2F^-0.08 and C_S=3C_V is selected to determine the modal ratio coefficient, and the design flood results obtained have the highest accuracy and the smallest error, which is in line with the characteristics of the Lanzhou area, and can provide a reference for the selection of the calculation method of flood in a small watershed.更多还原