Research on the project critical activity uncertainty risk assessment

In the engineering project, critical activities may lead the system to huge risk and even failure. Probabilistic risk assessment is closely related to reliability analysis. This paper defines uncertainty importance measure of the project's activities time and analyzes the specific analytical steps of uncertainty importance measure. Time may affect the whole project's risk; meanwhile cost and other factors will also work. So this paper proposes a methodology for the researching on uncertainty importance risk analysis of time and cost jointly. The main steps are: (i) defining a covariance of the cost and time of the project activities; (ii) setting up the jointly uncertainty importance measure of cost and time; (iii) calculating the uncertainty importance and ranking the order of the critical activities by mathematics analytic method. An adapted case is studied to assess the proposed methodology.