An evolution analysis of the impact energy damage of collapsed rolling stones under strong earthquakes

The impact energy dissipation damage of rockfall triggered by strong earthquake is an important indicator of protection engineering design. In order to explore the evolution process of the rolling stone energy consumption damage during the impact process, the law of thermodynamics was used to analyze the energy transfer and dissipation during the impact. By defining the impact energy dissipation damage factor D and D_max, the theoretical model and applicable model of the rock impact energy dissipation damage are established. Combining engineering examples and back-calculating the ultimate impact force to demonstrate and analyze the model, a generalization and application of the model is proposed. The damage process of the impact energy of the rolling stone satisfies the first law of thermodynamics. The energy mainly contributes to the accumulation of the elastoplastic potential energy of protective engineering. D_max is affected by the rolling stone mass, elastic modulus, initial velocity of ejection, maximum impact force, and effective area, etc. The maximum impact force continues to increase, and the limit impact energy dissipation damage factor increases. When the curve reaches the intersection point C (1031 kN, 0.9965) of the linear function and the parabolic function image, the curve has an inflection point. The model is extended to obtain the evolution function curve of the impact energy dissipation

damage in a generalized range. In the whole process of the impact energy dissipation damage, there are two damage inflection points at the critical position of the three stages of damage response, damage linearity, and damage progression. As the mass of the rolling stone increases, the maximum impact force increases, and the limit impact energy dissipation damage factor curve first decreases parabolically, then increases linearly, and finally increases parabolically until it reaches infinitely close to 1. A quantitative analysis of the damage nature from the view of energy point is of great significance in the exploration of energy dissipation mechanism of the rolling rock movement process and the design of protection engineering.