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

Table 2

Deformation characteristics of granite samples.

Sample no.	Secant Young’s modulus (MPa)		Tangent elasticity modulus (MPa)		Poisson’s ratio
	Single value	Average value	Single value	Average value	Single value	Average value
DY1	19493.8	18959.6	25023.9	24713.3	0.26	0.26
DY2	17478.5		26075.2		0.25
DY3	17698.4		26302.5		0.31
DY4	21167.7		21451.6		0.21