Influence of Water-Resisting Layer Thickness on Fracture Evolution in Karst Tunnel and Control Measures

Table 1

Mechanical parameters of optimized rock mass.

Limestone rock parameters	Density (kg/m^3)	(GPa)	Poisson’s ratio	Cohesion (MPa)	Internal friction angle (°)	Tensile strength (MPa)
	2500	10	0.25	12	35	11
Limestone joint parameters	Normal stiffness (GPa)	Tangential stiffness (GPa)	Internal friction angle (°)
	10	10	30