Abstract: In the aim of quantifying the evaluation of construction fatigue risk and improving construction safety, a fuzzy comprehensive evaluation method improved by cloud model was proposed to assess the construction fatigue risk of high-risk operationsin hydropower project.Three digital features Ex, En, and He were taken to substitute the comprehensive evaluation matrix and the weight matrix in traditional fuzzy comprehensive evaluation method.Fuzzy membership function was substituted by normal cloud model to calculate the ratings of risk possibility. The evaluation result was visualized by using forward and reverses clouds together.The method was applied to the evaluation of fatigue risk of high slope operations in a hydropower project.Results showed that the fatigue risk level of high slope operations is 5.419, which belongs to moderate risk but obviously closer to big risk. The randomness, fuzziness and subjectivity of the evaluation body are comprehensively considered by using this method.

Key words: hydropower project construction, high-risk operations, cloud model, fatigue risk, quantitative evaluation