In Situ Stress Inversion and Distribution Characteristics of Tunnel Based on Numerical Simulation and Neural Network Technology

Table 1

Rock block strength.

Lithology	Uniaxial compressive strength (MPa)	GSI index	Rock integrity coefficient	Blasting damage coefficient	Elastic modulus (GPa)
Thick carbonaceous slate	22	73	12	0.5	14
Thin layer carbonaceous slate	19	55	10	0.5	12
Porphyry	112	75	10	0.5	35
Basalt limestone interbedding	130	46	10	0.5	38