大孤山铁矿微差爆破延期时间的优化研究

为确定大孤山铁矿微差爆破的合理微差延期时间,借助有限元软件ANSYS/LS-DYNA对双孔微差爆破进行二维数值计算。根据模拟计算结果,对大孤山铁矿铁矿石爆破推荐的合理微差延期时间为:若使用高精度非电导爆管雷管爆破,孔间和排间微差时间应分别为25ms和65ms;若使用数码电子雷管爆破,孔间和排间微差时间应分别为35ms和70ms;试验表明,利用推荐的延期时间进行爆破,可使爆堆块度更加均匀,提高了爆堆的松散性及电铲装车的效率。

Delay Time Interval Optimization of Double Holes Millisecond Blasting in Dagushan Iron Mine

In order to determine the reasonable delay time intervals of millisecond blasting in Dagushan iron mine,the a two dimensional numerical simulation of double holes millisecond blasting was carried out by use of finite element software ANSYS /LS-DYNA.According to the simulated result,it was recommended that foe the millisecond blasting in Dagushan iron mine if using high-accuracy non-electric detonator with Nonel tube the time intervals of inter-hole and inter-row delay initiation should be 25 milliseconds and 65 milliseconds respectively,if using digital electronic detonator they should be 35 milliseconds and 70 milliseconds respectively.The experiment showed that the use of recommended delay initiating time intervals can make fragment size of blasting more even,improve the loosenss of blasted muckpile and the efficiency of electric shovel.