Study On Vibration Propagation Law And Vibration Reduction Measures Of Air Explosion In Explosion Tower

In order to understand and grasp the explosion tower mount propagation law of ground vibration reduction tower in the air,suspended air influence experiment to the precision testing instrument,provides the reference basis for the blasting vibration control of laboratory safety management and similar engineering effect.This paper from the explosion tower vibration experiment,the conversion mechanism of airburst tower surface vibratio n tests and other properties of the surface vibration waveform analysis of the analysis system analysis of the explosion tower airburst test data,draw conclusions as follows:(1)The explosion shock wave incident tower airburst,increase the peak overpressure with blasting distance decreases,the average wave overpressure is about 1.2 times the average peak overpressure of incident wave,reflection wave average velocity is about 1.5 times the average velocity of the incident waves.The relationship between overpressure,shock wave impulse and the ground vibration velocity peak in the explosion tower is established.(2)In the explosion tower,the damping ditch and foam concrete slab will not change the rule of surface vibration velocity.The surface vibrat ion velocity of the explosion tower is vertically > radially > tangentially.The surface vibration velocity increases with the increase of the charge quantity,and is less affected by the suspension height of the charge.In the formation cavity and non dense area,the surface vibration velocity will suddenly increase.(3)When the foam free concrete slab is used,the damping ratio of the damping ditch decreases with the increase of horizontal distance.The average damping ratio of the damping ditch to the horizontal direction is 40%-70%,and the vertical damping rate is less than 30%.The foam concrete slabs have damping effect on the surface vibration velocity of the non damping ditch side,and the horizontal,radial and vertical damping rates are 47.1%,38.5% and 47.4% respectively.(4)It is found that the attenuation coefficient and the attenuation index of the Sadovsky formula are 13.3-93.6 and 1.65-2.56 respectively.The regression goodness coefficients are all greater than 0.92,while the goodness-of-fit coefficient of the Sadovsky formula is less than 0.70.(5)Referring to the vibration safety allowance standard of "the equipment in the central control room of the hydropower station and power plant in operation" in the "Blasting Safety Regulations"(GB6722-2014),the safe allowable distance between the precision instruments and equipment adjacent to the explosion tower and the explosion source should be greater than 13 m.(6)The ground vibration energy in the explosion tower is mainly concentrated near the main frequency band.The larger the frequency band is,the smaller the vibration energy is,the larger the dose is,the more concentrated the main frequency band is,but the energy ratio of the main frequency band of the damping groove side is larger than that of the non damping groove side.