Integrated Treatment Technology of Storage-Mining Inclined Goaf under Expressway

Table 3

Comparison of two drilling methods.

Content of the test	Drilling method
	Rotary drilling (Z66-5 hole)	Impact rotary drilling (Z65-8 hole)
Work efficiency	Low drilling speed; low efficiency; large loss of bit	High efficiency; small loss of bit, prevent drilling deviation
Energy consumption	Low	High
Stratum adaptability	High applicability; applicable to quaternary, bedrock, caved zone, and coal mining cavity	Low applicability; unsuitable for broken bedrock and coal mining cavity
Grouting applicability	Less sediment; not easy to block grouting channel	Easy to block passage of the slurry