基于云模型的改进R=P×C风险评价法

Improved R = P × C Risk Assessment Method Based on Cloud Model

由于工程的复杂性以及施工过程中的不确定性,准确评价工程风险的难度在不断增大。R=P×C风险定级法是一种能够综合考虑风险事件概率和后果的风险评估方法,但在评估过程中难以处理工程领域普遍存在的不确定性问题。本文提出了基于云模型的改进R=P×C风险评价方法。该方法通过云模型对评估中P和C存在的不确定性因素进行模拟分析;结合专家群决策对定性概念的模糊性和随机性进行有效集成,实现定性和定量相互间的转换;利用云模型的不确定性推理技术,统筹考虑风险事件本身及推理过程的不确定性,最终确定风险评价等级R的云模型;并运用到武汉地铁盾构施工风险评价中取得良好效果,可为同类复杂工程安全管理提供决策参考。

Because of the complexity of the project and the uncertainty in the process of construction,the difficulty of accurate evaluation of project risk is increasing.R =P × C risk assessment matrix method is a risk assessment method,which synthetically considers the probability and consequences of the risk events.However,it is difficult to cope with the uncertainties with this assessment method,which widely exist in the current field of engineering.In this paper,R =P × C risk evaluation model based on cloud model was introduced to conduct the risk evaluation.The cloud model was introduced to the simulation analysis on the uncertainties of P and C.And in combination with expert-group decision,the fuzziness and randomness of qualitative conceptual were effectively integrated,and the mutual conversion between qualitative and quantitative was realized.Furthermore,by cloud model uncertainty reasoning,the uncertainties of risk event itself and the reasoning process were comprehensively taken into consideration.As a result,the R cloud model was identified.Finally,a case study was provided which successfully used the developed risk evaluation model during the metro tunnel construction in Wuhan and achieved good results.This result can provide a reference to decision-making for the similar complex engineering safety management.