Experimental Research On The Characteristics And Propagation Law Of Electric Explosion Vibration Wave Of Mortar Material

Explosive explosion and mechanical cutting are the main excavation methods of current rock engineering.However,explosive rock breaking has great explosion disturbance,easy to produce toxic and harmful gas and other hazards,and the control is relatively strict,and mechanical cutting is difficult to apply in hard rock engineering.Therefore,new rock breaking methods such as microwave rock breaking,carbon dioxide breaking rock,and pulse discharge rock breaking have gradually received attention from related scholars.At present,electric explosion rock breaking based on high-voltage pulse technology is still in the preliminary test stage.The characteristics and propagation rules of the vibration wave generated by pulse discharge rock breaking are still unclear,and the explosion vibration is an important inducement of rock mass disasters,so electric explosions are studied.Vibration characteristics and propagation laws are extremely necessary.This article designed and carried out a series of electric explosion experiments to study the characteristics and propagation laws of electric explosion vibration waves,in order to lay the foundation for electric explosion rock breaking in actual mine production.The main work includes the following parts:(1)The influence of the shape of the metal wire explosion source(straight wire,coiled wire)on the characteristics and propagation laws of electric explosion vibration waves.The length of the straight wire and the coiled wire is designed to be 50mm,and the characteristics of the electric explosion vibration wave under the different shape of the explosion source are studied.The results show that under the same charging voltage,the shape of the explosion source is different,the discharge distance between the electrodes and the plasma discharge channel formed are different,so that the peak vibration speed and main frequency of the electric explosion straight wire are larger than that of the coil wire.(2)The influence of charging voltage on the characteristics and propagation laws of electric explosion vibration waves.Keep the length of the straight wire at 50mm and the design voltage at 15kV,20kV,25kV,30kV,and study the characteristics of electric explosion vibration waves under different voltage conditions.The results show that as the charging voltage increases,the peak vibration velocity and main frequency of the electric explosion vibration wave also increase,and as the rising edge time of the current waveform decreases,the main frequency increases accordingly.(3)The influence of wire length on the characteristics and propagation laws of electric explosion vibration waves.The designed charging voltage is 25kV,and the length of the explosion source straight wire is 10mm,30mm,50mm,70mm,respectively,to study the characteristics of electric explosion vibration wave under different wire length conditions.The results show that as the length of the straight wire increases,the peak vibration velocity and main frequency of the electric explosion vibration wave also increase,and as the total duration of the current waveform oscillation decreases,the main frequency increases.(4)The influence of the structure on the propagation law of electric explosion vibration wave.The length of the designed straight wire explosion source is 50mm,and the charging voltage is 15kV,20kV,25kV,and 30kV.The influence of the structure on the vibration wave characteristics of electric explosions is studied.The results show that the peak vibration velocity and main frequency of the vibration wave after passing through the structure surface are both occurred Larger attenuation,and as the voltage increases,the attenuation rate becomes larger and larger.(5)Compare and analyze the differences between electric explosion,chemical explosion and mechanical vibration wave.It is found that the duration of the electric explosion vibration wave is 30ms,the main frequency is the highest,and the attenuation is the fastest;the duration of the chemical explosion vibration wave is 300ms,followed by the main frequency;the mechanical vibration wave lasts 150ms,and the main frequency is the smallest.