Study On Dynamic Stability Of Native Landscape Balance Rocks Under Blasting Load Based On Discontinuous Deformation Analysis Method

As a peculiar geological phenomenon,landscape balance rocks appear all over the world which are in the state of static or dynamic limit equilibrium for a long time.They are very sensitive to external artificial disturbance,such as surrounding blasting engineering construction,which may destroy their equilibrium state and even lose their stability.Based on the stability analysis project of native landscape balance rocks under blasting load in Jinyun Pumped Storage Power Station of Zhejiang Province,this paper systematically studies the dynamic response of landscape rock under blasting vibration by integrating UAV aerial modeling,field rock mechanics test,blasting vibration monitoring analysis and dynamic stability calculation based on discontinuous deformation analysis method.The main contents are as follows :(1)Traditional manual measurement method cannot accurately describe the complex geometry of landscape balance rocks,and most of the landscape rocks are located in dangerous areas such as cliffs,which are difficult to measure and has huge potential safety hazards.To solve this problem,a method combining unmanned aerial photography with software modeling is proposed to obtain the main geometric features of landscape equilibrium rocks.Compared with traditional measuring methods,this method can more accurately identify key information such as boundary of balancing rocks,occurrence and contact area of contact surface between balancing rock and base,improve the stability evaluation of balancing rocks from qualitative to quantitative level,and provide necessary geometric information for subsequent numerical calculation.(2)Blasting vibration monitoring is carried out on representative landscape balance rocks(Ling Xiao rock,Wen Tian rock,Chao Tian rock),and micro-vibration test data is obtained.The propagation and attenuation law of blasting seismic wave is analyzed,and the dynamic response of balancing rocks under seismic wave generated by different blasting forms is studied,which provides complete vibration input data for subsequent numerical analysis.(3)The stability of landscape balance rocks are compared and analyzed by equivalent static balance method and discontinuous deformation analysis method.The discontinuous deformation analysis method constrains the input of displacement by the large stiffness method and uses the rigid foundation as the bottom boundary condition.Compared with the traditional equivalent static method,the dynamic response characteristics and failure mechanism of the whole base and balance rock during vibration can be simulated more truthfully.The results show that the stability of Ling Xiao rock and Wen Tian rock is poor,and Chao Tian rock has a large safety margin.At the same time,the dynamic responses of the Ling Xiao rock under rigid boundary conditions and viscous boundary conditions are compared and analyzed,and the overall trend of the two is consistent.The rationality of the rigid boundary condition is proved.