大坝可接受风险水平确定方法研究

Study on methods for determining acceptable risk level of dams

F-N曲线法是一种通过直观图解描述风险频率(F)与后果(N)间关系的曲线,常与最低合理可行(as low as reasonably practicable,ALARP)准则相结合来确定社会风险可接受水平。现行方法中存在参数的确定缺乏理论依据、主观性强,且对于不同地区、不同风险类别通用性差等问题。本文针对上述问题提出了融合风险矩阵的改进F-N曲线。通过风险矩阵有效衔接现有风险规范,并提出了风险单元等级划分定性与定量相结合的方法,基于此将风险矩阵转化为F-N曲线。在大坝可接受风险水平研究的基础上,阐述了该方法的具体实现过程,并对比分析了与传统方法的差异和联系,比较结果说明改进后的F-N曲线较传统曲线更加规范、合理,且易于推广应用到其他类型的风险研究与计算中。

A F-N curve is an intuitive curve for describing the relationship between risk frequency(F)and consequence(N),and it is often combined with the as low as reasonably practicable(ALARP)criterion in determination of the acceptable level of social risks.The previous F-N curve methods suffer from several drawbacks,such as lack of theoretical basis,strong subjectivity,and poor generality for different regions or different risk categories.This paper develops an improved F-N curve through combination with a risk matrix.We integrate the risk criteria into a risk matrix and develop a method of rating the matrix elements by qualitative and quantitative evaluation,and then the risk matrix can be transformed into a F-N curve by using this method.To demonstrate its use,acceptable risk levels of water dams are calculated and compared with those of the traditional method.The results show that the improved F-N curve is more standard and more reasonable and is easy to apply to other types of risks.