Optimal blasting parameters predicted by rock mass properties - Engineering geological approach

摘要

The paper deals with the results of explorations in the tectonic fabric of rock masses, results of geophysical exploration and the blasting parameters that have optimal effects in open pits and quarries. Three factors control the fragment size distribution: the rock structure, the quantity of explosive and its distribution within the rock mass. Results of engineering-geological research are significant for the optimization of blasting parameters. These data are showing an objective picture of rock mass, and they are as follows: statistics of density of discontinuities, determination of "GSI", Hoek-Brown empirical criterion for strength of rock mass and "in situ" determination of mechanical parameters, including geophysical survey data. The strength of rock mass decreases with the increase in frequency of joints and the deformability of rocks depend on their orientation. It is the interaction between the rock mass and stresses generated due to explosive detonation, which may produce favorable or harmful blasting results.