Research On Propagation Of Blasting Crack Between Adjacent Blast Holes In Rock

Based on the full knowledge of the mechanism of rock fragmentation, this paper shows the dynamic evolution process of propagation and coalescence of blasting crack between adjacent blast holes with the help of numerical simulation technology, and analyzes the influence law of related factors on blasting effect. It is of great significance to the enrichment and improvement of the mechanism on smooth blasting. Specific research contents and results are as follows:(1)This paper proceeds from rock blasting theory, the mechanism of rock blasting cracking, the explosion action from charge in infinite rock and the rock failure mechanism of explosive stress wave and blasting gas are researched respectively in this paper, and calculation method of related blasting parameters are concluded. The rock cracking propagation is analyzed by using the numerical simulation technology.(2)The effect of adjacent hole blasting under different hole spacing was analyzed. Base on the theoretical analysis and numerical simulation results, the reasonable hole spacing of adjacent rock holes which can make good effect of crack penetration are obtained, and the results are consistent with the theory of our predecessors.(3)The calculation method of radial non-coupling coefficient has been studied based on blasting mechanism of non-coupling charge blasting. The result shows that using reasonable coefficient can effectively promote the expansion and penetration of cracks while reduce cracks in the other direction.(4)Research on the effect of adjacent holes blasting under the different detonating delay time shows that the cracking quality of directional fracture blasting can be improved effectively while minimizing time interval, and avoid the occurrence of back break in perimeter holes blasting, thus to improve the effect of smooth blasting.(5)Result of research on the effect of adjacent holes blasting with empty hole shows that the empty hole can effectively guide the cracks expanding and penetrating between adjacent holes and then improve the effect of smooth blasting.