Inversion Study of Mechanical Parameters of Tunnel Surrounding Rock Based on Similar Test

Table 4

Parameter inversion results.

Vertical load (kN)	Modulus of elasticity (MPa)	Amount of change	Cohesion (kPa)	Amount of change	Poisson’s ratio	Amount of change	Angle of internal friction (°)	Amount of change
0	50	—	16	—	0.3	—	31	—
10	50.70	+1.40%	18.01	+12.56%	0.29	−3.33%	31.03	+0.01%
20	49.97	−0.06%	14.87	−7.06%	0.27	−10.00%	31.42	+1.35%
30	50.79	+1.58%	17.66	+10.38%	0.31	+3.33%	29.29	−5.52%