Optimized Analysis Method for Evaluating the Shear Strength Parameters of Rock Joint Surfaces

Table 4

Analysis results of the shear strength parameters of joint specimens.

Analysis method	c (MPa)	ϕ (°)
Extreme value line 1	0.98	23.12
Extreme value line 2	−0.40	52.49
Conventional multiple-specimen method	0.05	45.15
Single-specimen method	0.28	40.80
Optimization method	0.29	40.85