Analysis on Influence Factors of Roadway Instability in High-Stress, Steeply Inclined Extra-Thick Coal Seam

Table 1

Drawing test results of deformed steel bars.

Number	Original length of stretching section (mm)	Stretch length (mm)	Rod diameter (mm)	Elongation of rod (%)		Pull-out resistance (kN)
				Actual measurement	Mean value	Actual measurement	Mean value
1#	205.50	39.28	20.05	19.11	20.61	188	189
2#	203.20	42.40	20.10	20.86		185
3#	201.56	44.10	20.08	21.87		194