Abstract：Hydrological and geological parameters are important factors for planning and design works of hazard prevention in hillslope.However,these parameters usually exist uncertainty for hazard prevention works.This may results the risk of hazard assessment and the low reliability for planning and design of hazard mitigation.In this paper,the basic concept of risk and reliability analysis are introduced and the two cases study for debris-flow occurrence and design discharge of hyperconcentrated flow by the risk and reliability analysis are presented.
2006, Vol. 4 
