露天台阶深孔爆破根底和大块的成因及解决措施

The Cause and Solving Measure of Produced Root Bottom and Big Ore Block in Expose Step Deep Hole Blasting

山东镁矿对露天台阶深孔爆破生产中的大块和根底进行分析，发现其成因是孔网参数和超深值不合理；受矿岩节理和裂隙发育影响；因矿岩涌水使穿孔装药受影响等．解决的措施是加强现场管理、确定合理的孔网参数，采用合理的分段装药和起爆顺序等．

Through analysing the big block and root bottom produced in expose step deep hole blasting of Shandong magnesite mine,found that the cause are nonsuitable hole net parameter and extra deep value and are under the influence of crack growth and charging in hole with rock leaking water,etc.The solving methods are strengthening management at field,determining reasonable hole net parameter,taking reasonable section charge and blasting sequence,etc.