A New Unified Solution for Circular Opening considering Different Strength Criteria and the Postpeak Elastic Strain Form

Table 2

Geometrical and physical parameters of circular opening.

Parameters	Rock type by Park and Kim (2006) [10]
	Hard rock	Soft rock
Radius of opening, (m)	1	1
Initial stress, (MPa)	1	1
Internal pressure, (MPa)	0	0
Young’s modulus, (MPa)	50,000	5000
Poisson’s ratio,	0.2	0.2
Shear modulus, (MPa)	20833	2083
(MPa)	0.173	0.276
(deg)	55	35
(MPa)	0.061	0.055
(deg)	52	30