The Study on Large-Diameter Drilling Prevention Method of Rock Burst in the Xinxing Coal

Table 1

Physical and mechanical parameters of 58-layer coal and rock samples.

	Sample No.	Specimen size	Cross-sectional area; cm^2	Damage; Load; kN	Uniaxial compressive strength; MPa	Average uniaxial compressive strength; MPa	Apparent density; kg/m^3	Average apparent density; kg/m^3
Roof	1		19.6	195.42	99.705	99.2842
	2		19.6	192.46	98.192
	3		19.6	196.18	100.093
	4		19.6	205.43	104.813
	5		19.6	183.49	93.618
Coal	1		19.6	46.79	23.873	18.613
	2		19.6	38.68	19.734
	3		19.6	36.54	18.644
	4		19.6	29.39	14.993
	5		19.6	31.03	15.830		1.29 × 10^3
Bottom plate	1		19.6	215.27	109.832	100.2482
	2		19.6	187.76	95.797
	3		19.6	200.83	102.462
	4		19.6	193.77	98.861
	5		19.6	184.81	94.289