Research Of Vibration Effects And Control Of Blasting With Precise Delay Time Near Slope

In recent years,with the rapid development of national economy,the controlled blasting technology is widely used in mining,railway and highway construction of embankment engineering,resulting in a lot of artificial high steep slope.At the same time,the scale of engineering blasting is increasing largely and the environment became more and more complex,which is a great challenge for the security and stability of the slope.Study the vibration response of rock slope in precise time delay control blasting and its influence on mines surrounding structures has a very important significance to promote the development of accurate delay control blasting technology,guiding engineering blasting construction and protect the safe of the environment near blasting area.Theoretical analysis,model test,numerical simulation and engineering test monitoring are combined to study the vibration intensity of rock slope under millisecond blasting in different hole delay time,and the influence on mines surrounding structures under precise time delay control blasting.Firstly,the millisecond blasting theory and accurate delay control blasting technology are elaborated,and the method of delay time optimization based on the principle of linear superposition of blasting seismic wave and energy distribution are analyzed.Secondly,the experiment of indoor concrete slope for accurate delay millisecond blasting were done by using Lux No.1 digital electronic detonator,and the blasting vibration waveform of specific measuring point under1~5ms different delay time were earned,The results show that: the best delay time for damping effect is 2ms for the model slope under the experimental conditions.Thirdly,the ANSYS / LS-DYNA software was used to realized the process of hole by hole initiation of rock slope by numerical simulation,and the vibration velocity-time curve of measuring point under 1~5ms different delay time were also earned;analysis and compared the numerical simulation and model experiment,found two results are consistent,precise time delay controlblasting vibration effect was verified.Finally,the experiment for accurate delay millisecond blasting based on the blasting excavation in Yankou Quarry,Shiyan City was conducted,analyzed the vibration response of the houses and multi-storey buildings in different floor.The results show that:the minimum blasting vibration of the house which away from the explosion area 300 m were happened when the delay time sets20ms;the multi-storey buildings' vibration velocity in the vertical direction increased by about 45%with the floor height while that in the horizontal direction decreased by about 33% with the floor height.