Equivalent modeling of energy dissipation in impact and rock blasting fragmentation of frozen sandstone
In order to investigate the blastability of frozen rock in the cold region blasting project,SHPB impact tests were conducted on frozen sandstone with different moisture contents.In addition,combined with the energy distribution of columnar explosives,the characteristics of frozen sandstone impact and blasting rock-breaking energy dissipation characteristics were studied.Based on this,the unit consumption model of explosive in frozen sandstone blasting was proposed,and the numerical simulation method was used to further modify the model.The results show that:(1)as the moisture content increases,the degree of damage to the sandstone specimens gradually increases;at the same moisture content,the degree of damage to the frozen sandstone specimens is weaker than that of the normal temperature sandstone specimens.(2)As the moisture content increases,the dissipated energy of normal temperature and frozen sandstone specimens gradually decreases;at the same moisture content,the impact dissipated energy of the frozen sandstone is higher than that of the normal temperature.When the moisture content is0w,0.25w,0.50w,0.75wand 1.00w,the increase of dissipated energy is about 21.6％,64.9％,80.3％,78.2％,and 83.3％respectively.(3)The fitting equation of unit explosive consumption and moisture content of sandstone is obtained by equivalent calculation of the impact rock breaking energy of sandstone and the blasting rock breaking energy of columnar emulsion explosive.(4)Based on the simulation results of blasting crater test,the cubic root similarity law was used to correct the unit explosive consumption and a modified unit explosive consumption model of sandstone blasting is obtained.
rock mechanicsfrozen sandstoneSHPB impact testenergy dissipationSPH algorithmunit explosive consumption
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