通过对特大型泥石流灾害发生的思考,详细分析了蒋家沟1995—1997年43场泥石流暴发的不同权重的前期和始发日降雨量与泥石流产沙规模的关系。分析结果表明:泥石流的产沙规模与不同权重降雨的入渗范围、深度的土体极限应力状态(C、Ф、P,)有关。根据不同权重的前期和始发日降雨量与泥石流产沙规模的关系,可以将泥石流分为:土力型(A)和迳流型(B)两大类型。土力型(A)泥石流有24场占总样本的55.81%,而其产沙量却占样本总产沙量的85%。迳流型(B)泥石流有19场占总样本的44.19%,但该类泥石流的产沙量只占样本总产沙量的15%。
The difference of sediment transport scale of debris flows are been to analyze in this article in detail, based on debris flow occurrence in 43 times from 1995 to 1997 under different weight of precedent and daily critical rainfall. Analyzed results indicated that sediment transport scale of debris flows is relative to the limit stress state ( C, ~, P~ )of soil in stole and depth to soil by different weight rainfall. Debris flows can been divided : soil machanism type (A) and runoff type (B). Debris flows in A type had occurred 24 times,which were accountd for 55.81 % of total stylebooks, the sediment transport quantity was aecountd for 85 % of total sediment transport. Debris flows in B type had occurred 19 times, which were accountd for 44.19% of total stylebooks, the sediment transport quantity was accountd for 15% of total sediment transport. Debris flows of fill preliminary (or called precedent )rainfall (A1) in A type had occurred 14 times, which were accountd for 32.5 % of total stylebooks, mean weight of rainfall is 2.4, the sediment transpor scale is the most, which was accountd for 48 % of total sediment transpor.