Effect of Uncoupled Charge Coefficients on Rock Blast Damage
A suitable charging structure in blasting engineering can effectively improve the utilization rate of explosives and thus improve the blasting effect.Based on the RHT(Riedel-Hiermaier-Thomamodel)dynamic response mechanics relationship,ANSYS/LS-DYNA software was used to study the effect of the uncoupling coefficient K on the blasting load of rock body under the condition of eccentric uncoupled charge and the damage of rock body during blasting.The effective stress,vibration velocity,seismic wave energy and damage conditions under uncoupling coefficients K=1.0,1.5,2.0,2.5,3.0 and 3.5 were analyzed by establishing a single-hole eccentric uncoupled blasting model.In addition,the relationship between burst center distance l and damage degree D,mass vibration velocity PPV and burst center distance l,and vibration velocity vpp and damage degree D under different conditions of uncoupling coefficients K were investigated.The results show that with the increase of the uncoupling coefficient K,the effective stress and peak vibration velocity of the coupled and uncoupled sides and the peak energy of the seismic wave decreases slightly.The range of the crushed zone and the fracture zone decreases gradually,and the radius of the damage in the crushed zone is larger than the rate of decrease in the fracture zone.The damage degree of rock body and the mass vibration velocity vpp are gradually reduced with the increase in the burst center distance.The greater the particle vibration velocity vpp is,the larger the damage degree is.When vpp reached 50.4 cm/s,the damage variable D in the rock body reached the damage failure threshold of 0.19.When vpp>140.6 cm/s,the damage degree D>0.80.
rock damageparticle vibration velocityeffective stresscharge structureblast center distanceuncoupling coefficient
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万方数据
维普
