Hazard Assessment Of Potential Debris Flow In The Lower Reservoir Area Of Xingtai Pumped Storage Power Station

In order to actively respond to the national "carbon emission peak,carbon neutrality " policy,the development and construction of pumped storage power stations ushered in significant development.Generally,the location of the pumped storage power station is often in the mountain area.As a frequent geological hazard in the mountain area,the risk assessment of the debris flow in the location area needs to be carried out during the location of the pumped storage power station.This paper takes the potential debris flow gully in the lower reservoir of Xingtai pumped storage power station as the research object,and studies the physical geography and geological environment of the potential debris flow development,as well as the formation conditions,development characteristics and characteristic parameters of the debris flow in the study area through field investigation and analysis.The hazard assessment of debris flow is carried out through the mathematical model cloud model,and then the potential debris flow gully in the lower reservoir area is numerically simulated with FLO-2D software to explore its dynamic characteristics.According to the simulation results,the potential debris flow in the lower reservoir area is controlled and numerically simulated.The main research results are as follows:(1)Based on the on-site investigation and remote sensing interpretation,combined with the pre-feasibility study report of Xingtai pumped storage power station,the geographical location information and development geological background of the lower reservoir area of Xingtai pumped storage power station,as well as the overall characteristics of the small watershed and the characteristics of each gully in the lower reservoir area of Hengling were obtained.(2)According to the field survey,the basic characteristics of the valley in the lower reservoir area are analyzed,and the valley in the lower reservoir area is judged as a potential debris flow gully according to the parameters such as the amount of unstable material sources in the valley,the longitudinal slope gradient and the rainfall intensity.The lower reservoir area of Hengling Reservoir of Xingtai Pumped Storage Power Station may erupt with sparse debris flow,and the degree of debris flow is mild.By selecting reasonable evaluation indicators,the risk assessment of potential debris flow in the lower reservoir basin is carried out using the combination of fuzzy set improved analytic hierarchy process and entropy method.The assessment shows that the 7 # and8 # ditches in the lower reservoir basin of Hengling are moderately dangerous,and the rest are slightly dangerous.(3)The FLO-2D numerical simulation software is used to carry out numerical simulation on 9 gullies that may affect the pumped storage power station,and the flow velocity and maximum accumulation depth of each gully are obtained.According to the dynamic characteristics after simulation,the risk assessment model is established,and the risk zoning of Henglingxia reservoir basin under different rainfall frequencies is obtained.(4)Based on the previous analysis results,the prevention and control suggestions for the potential debris flow in the lower reservoir area of Hengling Reservoir of Xingtai Pumped Storage Power Station are as follows: retaining dam engineering is adopted for the treatment of No.8 gully,and biological treatment is adopted for other valleys.The numerical calculation method is used to simulate the reinforcement effect of retaining dam engineering treatment of No.8 ditch and optimize the reinforcement scheme.