English：

The construction of a cavern group of pumped storage power stations is often faced with complexrisk factors. It is urgent to construct a scientific and reasonable construction risk assessment model tosupport safe construction decision⁃making. In accordance with this, the construction risk assessmentmodel of the pumped storage power station cavern group based on the cloud model is constructed. Basedon the geological conditions and construction scheme of the cavern group of the Tongshan Pumped StoragePower Station in Hubei Province, a construction risk index system combining qualitative description andquantitative classification of index risk grade was established from the aspects of engineering geology,natural environment, design and construction, and management. The Analytic Hierarchy Process was usedto determine the index weight. Based on the cloud model theory, the cloud digital features wereestablished, and the comprehensive evaluation cloud was generated to complete the risk leveldetermination. The results indicate that the comprehensive cloud digital characteristics of the project are(48.178, 6.495, 1. 101), and the similarity with the “lower risk” level is the highest (0. 207), which isin good agreement with the actual situation of the project. The validity and applicability of the model in theconstruction risk assessment of the cavern group of pumped storage power stations are verified.