Seismic Effect Of Open-pit Blasting On Undulating Terrain With Large Elevation Difference And Its Predictive Control

Blasting for excavation and blasting of high slope in undulating terrain with large elevation difference often has many problems,such as large blasting volume,large blasting scale,frequent blasting operations,blasting seismic effect and so on.Based on the high slope excavation and slope protection engineering of section GDK0+100-GDK3+534.45 of Yuhuai Railway,this paper aims at blasting construction of high slope in undulating terrain with large elevation difference.The blasting seismic effect and its control are studied.On the basis of testing and analysis of blasting vibration of high slope on undulating terrain with large elevation difference,based on Buckingham Theorem and combined with physical dimension analysis of factors influencing blasting seismic effect,empirical formulas of particle vibration velocity peak at uphill and back slope positions are derived and given,which are based on engineering undulating terrain with large elevation difference.The prediction model of blasting vibration velocity is used to control the blasting seismic effect of different buildings and structures affected by blasting vibration of relying projects,which ensures the quality and safety of blasting excavation of relying projects on high slopes.The main research content is as follows:(1)Regression analysis was performed on the monitoring data,the Sadovsky empirical formula of peak particle vibration velocity in vertical direction,horizontal longitudinal direction and horizontal transverse direction is obtained.The attenuation law of particle vibration velocity and frequency is studied,and the frequency spectrum characteristics of blasting seismic structure response caused by soil and rock blasting in different locations and structures are obtained.(2)On the basis of theoretical analysis of factors affecting blasting vibration and structural blasting vibration response,risk assessment of blasting construction of high slope in undulating terrain with large height difference is carried out,and the conclusion that the main risk source of the project is blasting vibration is obtained.(3)Based on Buckingham's theorem and physical dimension analysis of factors affecting blasting seismic effect,empirical formulas of particle vibration velocity peak of uphill and back-hill slope based on elevation amplification effect are derived and presented,and a prediction model of particle vibration velocity peak of uphill and back-hill slope based on elevation difference is proposed.(4)Combining with the prediction model of particle vibration velocity peak value of uphill and back-hill slope based on elevation difference and other factors,the blasting seismic effect control of different buildings and structures affected by blasting vibration of relying engineering is carried out,which ensures the quality and safety of blasting excavation of relying engineering high slope.