Research On The Law Of Blasting Seismic Wave Propagation In Hejia Mining Area Of Gongchangling Open-pit Iron Mine

Blasting seismic wave produced by explosive explosion in rock can cause vibration of the rock medium particle and surface layer of soil when it propagates in strata,and the damage phenomenon and consequence caused by it are called blasting seismic effect.The blasting seismic effect is one of the main hazards of open-pit mine blasting.At present,most of the open-pit mine uses middle-deep hole blasting,and its salient characteristic is single hole charge high.Thus,the blasting seismic causes certain effect to the industrial buildings and houses around the blasting area inevitably.Because of the blasting seismic wave is the direct factor of blasting seismic effect.Therefore,the study on the Law of blasting seismic wave propagation has an important significance for control the harm caused by blasting seismic effect effectively.This paper on the basis of existing research results of the blasting seismic wave,takes production blasting in Hejia mining area of Gongchangling open pit iron mine as the research object,around the influence of blasting vibration on the surrounding villagers' houses,bases on the monitoring data,by the means of theoretical analysis and numerical simulation comprehensively analyzes the law of blasting seismic wave propagation.The main research contents and achievements are as follows:(1)Based on the monitoring data,analyzed the distribution characteristics of blasting seismic wave parameters from the blasting vibration velocity,vibration frequency and duration in Hejia mining area of Gongchangling open-pit iron mine.(2)By using the least squares method,regressed the attenuation formula of blasting vibration frequency and particle vibration velocity without considering the elevation amplification effect;by using multiple regression analysis,regressed the attenuation formula of particle vibration velocity considering the elevation amplification effect.It not only can be used to guide the blasting design,but also determine the maximum dosage of different blasting area.(3)Forecasted the particle vibration velocity and vibration frequency of villagers'houses closest to the mining area when near the eastern mining area slope position trench blasting by using the formula derived from regression,and adjusted the trench location proposal according to the results of the prediction.(4)By using ANSYS/LS-DYNA software simulated the ditching blasting process of II blasting area that has the greatest impact on the villagers'houses,calculated the particle vibration velocity of the villagers' houses closest to the mining area.Simulated and analyzed the two kinds of bench blasting scheme near the II blasting area,determined the reasonable scheme for bench blasting that two holes blasting at the same time,with the most number of initiation holes increased to two.