在分析有限物源的不同规模泥石流频率难以用暴雨频率这一单因素确定的前提下,提出用综合分析的办法确定其频率.以黑水县罗坝街沟1933年、1983年、1984年和1997年泥石流为研究物件,对其流量进行测量和分析计算.从降雨频率与泥石流频率的巨大差异,可知此类泥石流的暴发频率与泥石流的频率差别极大.从历史调查法,地震与土源和产流关系分析法和推理公式与水科院公式的计算类比推算出罗坝街沟1933年的泥石流远大于百年一遇,1983年的泥石流为百年一遇,1984年的泥石流为50年一遇,1997年泥石流为10年一遇.从一系列的分析计算可知,有限物源流域不同规模的泥石流频率的确定需要考虑多种因素,并进行综合分析.

As there are some problems to check the debris flow frequency with the precipitation frequency in earth source limited area. It is suggested that judging the frequency by comprehesive way. Applying the Loubajie valley debris flow in 1933, 1983, 1984 and 1977 as study cases we analyzed the basin characters, the debris flow basic nature. It is found that the debris flow frequency of Luojiba is different from the frequency of local precipitaion. Therefore we have to use the comprehensive way to check the real frequency of debris flow. First, the history of debris flow are gotten to check the debris flow frequency; Secondly, the carthquake frequency is studied and be used to compared the debris flow frequency; Thirdly different hydraulic calculation ways are used to calculate the debris flow frequency. At last it is make sure that the frequency of debris flow in 1933 is more frequent than 100 years a time; that of 1983 is 100 years a time; that of 1984 is 50 years a time and that of 1997 is 10 years a time.