Research On The Safety Risk Evolution Of Underground Cavern Construction In Hydropower Projects Based On The Cusp Catastrophe Theory

With the continuous increase of hydropower development and construction in Southwest region of China,most hydropower stations adopted the design and construction schemes of underground water diversion and power generation system due to the effects of its high altitude and complex geological and topographical conditions.Underground cavern,as a key component of the construction of the water diversion and power generation system,is very essential for hydropower project construction to implement successful,which includes exploring the safety risk factors existing in the construction process,simulating the evolution process of construction security risks,and judging the construction security status and preventing cavern construction safety accidents.In view of above,the influencing factors of safety risk in underground cavern construction of hydropower projects were explored based on the theory of accident cause and the perspective of construction units,and the corresponding cusp catastrophe model was established to analyze the evolution mechanism of safety risk in cavern construction.With the help of engineering cases,the catastrophe progression method was used to calculate the actual risk value,and the influence of single factor and multi factor risk evolution on the construction safety risk value was explored at the same time.The results were showed as follows:Firstly,the connotation and characteristics of the construction safety risk on hydropower project underground cavern were summarized.Based on the accident cause theory,the construction safety risks were divided into the unsafe human action and unsafe state of articles,and relevant risk factors were explored.The risk indicators were sorted by Likert scale according to significance,and the important risk factors were screened and the risk index system was established.Secondly,the applicability of catastrophe theory in the evolution of construction safety risk was introduced,and its catastrophe characteristics were analyzed.Human factors and physical factors were used as control variables,and then a cusp catastrophe model of construction safety risk in underground caverns of hydropower projects was constructed.After that,the risk evolution process was simulated,the model boundary was determined furtherly and the construction safety state was divided.Finally,the practical cases were combined with the construction safety risk index system of underground caverns of hydropower projects,and the value of the actual construction safety risk state is calculated by the catastrophe progression method.Then,the construction safety risk evolution model was built by software to analysis the impact of the single risk change and multiple risk coupling effects on the construction safety state,and explore the key risk factors affecting construction safety and its sensitivity.The corresponding preventive measures,control measures and emergency measures were put forward for the prophase,metaphase and anaphase of construction safety accidents,so as to provide countermeasures and suggestions for the construction safety management and control of underground caverns of hydropower projects.