Numerical Study on the Mechanism and Application of Artificial Free Surfaces in Bedrock Blasting of Shield Tunnels

Table 3

Results of uniaxial impact compression tests of granites.

Excitation pressure (MPa)	Sample no.	Average strain rate (s^-1)		Peak stress (MPa)		Peak strain
		Single value	The average	Single value	The average	Single value	The average
0.15	A-1	80.991	76.137	70.974	64.78	0.0021	0.0023
	A-2	63.173		68.236		0.0032
	A-3	83.269		60.498		0.0018
	A-4	82.367		58.867		0.0025
	A-5	70.236		65.324		0.0017
0.2	B-1	115.596	99.594	99.497	89.685	0.0031	0.003
	B-2	135.123		91.573		0.003
	B-3	110.829		75.323		0.0026
	B-4	131.671		89.989		0.0025
	B-5	120.346		92.043		0.0035
0.25	C-1	142.131	141.25	130.748	141.055	0.0041	0.0042
	C-2	152.041		140.079		0.0039
	C-3	144.572		144.217		0.0046
	C-4	138.201		149.461		0.0035
	C-5	129.311		140.771		0.0049
0.3	D-1	159.509	160.62	166.638	158.961	0.0049	0.0053
	D-2	175.639		176.693		0.0051
	D-3	160.438		138.864		0.0046
	D-4	158.268		152.368		0.0057
	D-5	149.235		160.235		0.0062
0.35	E-1	203.609	198.9	157.269	178.105	0.0058	0.0062
	E-2	196.089		201.446		0.0065
	E-3	207.223		183.247		0.0063
	E-4	189.324		170.236		0.0057
	E-5	198.235		178.327		0.0067
0.4	F-1	251.935	245.13	200.583	203.599	0.0091	0.0083
	F-2	247.507		215.491		0.0078
	F-3	237.496		193.679		0.0073
	F-4	226.157		208.623		0.0083
	F-5	262.548		199.623		0.0087