Annual risk assessment on high-frequency debris-flow fans

被引：10

作者：

Hu, Kaiheng ^{[1
,2
]}

Li, Yong ^{[1
,2
]}

Wei, Fangqiang ^{[1
,2
]}

机构：

[1] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China

[2] Chinese Acad Sci, Key Lab Mt Hazards & Earth Surface Proc, Chengdu 610041, Peoples R China

来源：

NATURAL HAZARDS | 2009年 / 49卷 / 03期

基金：

中国国家自然科学基金;

关键词：

Debris flow; Alluvial fan; Risk assessment; Annual loss ratio; Gamma function; Probability model; OREGON COAST RANGE; DEPOSITION; HAZARD; MODEL; WOOD;

D O I：

10.1007/s11069-008-9290-y

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

An empirical model of debris-flow risk assessment is developed to estimate annual loss ratio on high-frequency debris-flow fans where more than one hazard events occur every year. Based on observations of debris flows in Jiangjia Ravine, Yunnan Province, China, it is found that Gamma distribution is more appropriate for describing the annual frequency than the exponential distribution, which is supposed to be a good description of the low-frequency cases. Further analyses reveal that the two parameters of Gamma distribution can be explained, respectively, as the number of factors which dominate debris-flow occurrence and one-third of the mean annual frequency. Given the expectation of loss ratio is unchanged for each event we deduced a simple relationship between the expectations of one-event and annual loss ratios. Combined with the Gamma model, an equation is proposed to calculate the expectation of the annual loss ratio, which can be also used to assess the potential risk of fans formed by high-frequency debris flows.

引用

页码：469 / 477

页数：9

共 31 条

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