Structural response and safety analysis of large-size radial steel gate for hydropower station

Abstract

[Objective] Radial gates are crucial components in flood discharge structures for reservoirs and dams. Their structural safety and reliability are of great significance for achieving normal operation of reservoirs and dams and ensuring structural safety during flood seasons. To analyze the structural safety of the radial steel gate under multiple complex load conditions, a detailed 3D numerical model of the large-size radial steel gate was developed using ANSYS. [Methods] Taking the large-size radial steel gate in the Kafue Gorge Lower Hydropower Station as an example, the mechanical responses of the radial gate under three typical operating cases, e.g., closed, instant opening, and momentary open fault, were calculated. Then, the reasonableness of the 3D model and simulation process was verified through case comparisons. Moreover, the distributions and variation laws of displacement and stress of the radial gate under different operating conditions were further analyzed. The strength, stiffness, and stability of the main structure and fastening components of the radial gate were analyzed comprehensively. [Results] The result show that the case of momentary open fault constitutes the most critical operating condition for the structural safety of the main structure and the radial gate. Under this scenario, significant deformation and high concentration of equivalent stress are observed around the connection between the lower support arm and the gate leaf on the opening and closing force application side, which is identified as the dangerous part. Overall, the main structure and anchoring components of the radial gate meet the relevant requirements for strength, stiffness, and stability. [Conclusion] The results indicate that in the long-term service state of the radial gate, the dangerous part is prone to wear and has a risk of fatigue damage due to repeated opening and closing cycles. Comprehensive analysis suggests optimizing the design and reinforcing this structural area to meet the safety requirements under the most unfavorable conditions, thereby ensuring the long-term safety of the structure. The structural design of the radial gate is safe and reliable. This study ensures the structural safety of the large-size radial steel gate in the Kafue Gorge Lower Hydropower Station and can serve as a reference for the safety design of similar radial gates.

Keywords

radial steel gate / response rule / safety analysis / FEM simulation / hydropower station