立井冻土掘进爆破技术的研究与应用

崩落爆破通常承担整个立井冻土掘进爆破40 %～60 %的破土量。宽孔距崩落爆破能够增加自由面的有效利用、增强自由面应力波的反射拉伸作用和消除或减小冻土中的应力降低区。在理论分析的基础上进行冻土爆破漏斗模型试验，综合考虑爆破漏斗体积和爆破后两炮眼间最大凸量，初步认为炮眼密集系数 =1.5左右时较为合理。结合立井崩落炮眼成圈弧形布置和冻土所受夹制作用相对较大的特点，建议应在此基础上适当降低立井冻土崩落爆破炮眼密集系数，这在进一步的工程实践中得到了验证。

Study and application of frozen soil blasting technique in shaft

Breakout blasting often responds 40 %-60 % fracturing soil quantitative during the course of the whole frozen soil blasting tunneling in shaft.Wide pitch-row breakout blasting can increase the effective application of free face and consolidated reflection and tensile affection of free face stress wave and cancel or reduce the decreasing field in frozen soil.Theoretical analysis and model test of binocular explosive funnel have been presented to the most important parameter,dense coefficient of borehole in breakout blasting,and the volume of explosive funnel,v,and the maximal convex capacity,h,between two boreholes after blasting also has been thought synthetically.The authors think dense coefficient of borehole,m=1.5 is reasonable.Combined with the arc layout of breakout bore of vertical well and the feature of frozen soil with relative bigger restriction effect,the dense coefficient of borehole of breakout blasting in shaft suggested should be decreased rationally based on it,which was proved in further engineering practice.