沟床起动型泥石流的10 min降雨预报模型
Research on the 10-minute rainfall prediction model for debris flows
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摘要: 针对沟床起动型泥石流的诱发因素为高强度短历时的降雨,提出10 min降雨强度是这类泥石流暴发的关键。在1 h预报模型的基础上,基于云南蒋家沟的多年泥石流观测资料,修正了1 h预报模型的降雨参数,并得到了10 min降雨预报模型。10 min降雨预报模型在中国西部的其他流域,如云南浑水沟、贵州望谟县打易区域泥石流沟、四川三滩沟、四川雅安陆王沟和干溪沟、甘肃柳湾沟、甘肃马槽沟等流域的验证中,取得了较好的结果。10 min降雨预报模型是部分建立在泥石流的形成机理上的模型,并不是完全的统计模型,因此该模型也可以用于其他地区的沟床起动类型泥石流预报。Abstract: High-intensity short duration rainfall was the main triggering factor for the gully type debris flows which are triggered by a runoff induced mechanism. The 10-minute rainfall intensity is considered as the trigger. A revised prediction model with factors related to rainfall is introduced for this kind of gully type debris flows and applied to the Jiangjia gully. A 10-minute rainfall coefficient intensity is proposed based on the 1-hour prediction model, and the observational data of Jiangjia gully is presented. The model was successfully validated in debris flow gullies with the same initiation mechanism in other areas of west China. The generic character of the model is explained by the fact that its factors are partly based on the initiation mechanisms and not only on the statistical analyses of an unique variety of local factors. The research provides a new way to predict the occurrence of debris flows initiated by a runoff induced mechanism.