Abstract: Most balanced rocks are in limit equilibrium or basically stable state in natural conditions, but are prone to lose stability under external disturbance. The aim of this research is to protect the famous landscape balanced rocks in Jinyun Pumped Storage Power Station project area under blasting load. The fine three-dimensional numerical model of the balanced rocks was established based on unmanned air vehicle (UAV) photography and handheld camera photography. The geometric information and contact state of the balance rocks were obtained by using the numerical model, and the safety factors under sliding instability and toppling instability were acquired by analyzing the static equilibrium state and static stability. Moreover, the Discontinuous Deformation Analysis (DDA) method was employed to analyze the dynamic load stability of the balanced rocks under limit equilibrium state. The large stiffness method was adopted to input the velocity time history at the bottom of the model to simulate the measured vibration curve of the balanced stone base. By amplifying the input load, the allowable value of the horizontal vibration velocity of the base at instability state was obtained. In line with blasting safety standard, the allowable blasting vibration safety standard of balanced stone base is proposed to be within 0.20-0.40 cm/s.

Key words: :balanced rock, unmanned air vehicle, three-dimensional modelling, DDA, blast vibration