This study is performed to know the blasting mechanism and optimum fragmentation by the variation of the ratio of spacing and burden(S/W) and breaking areas(S×W) in Alter-nate Multi-row Hide Space hole pattern.
For the experiments, cement mortar spe...
This study is performed to know the blasting mechanism and optimum fragmentation by the variation of the ratio of spacing and burden(S/W) and breaking areas(S×W) in Alter-nate Multi-row Hide Space hole pattern.
For the experiments, cement mortar specimens are used.
The results are summarized as follows ;
① The optimum spacing to burden ratio to get the best fragmentation depends on the blast- ing area(burden×spacing) when concentration of charge is kept constant.
② The reduction of burden increases the cracking by reflected tensile stress wave.
③ Wide space hole pattern causes effective full crack development with less cut-off by the cracks of previous round.