Variation of Rock Mass Pressure during Tunnel Construction in Phyllite Stratum

Table 3

Fitting parameter range of rock mass pressure and settlement.

Function types	Basic form	Parameters	Value range
Logarithmic function			−10.127∼0.045
			−1.184∼0.005
			2941.362∼5151.256
Logistic function			0.003∼0.027
			0.046∼0.241
			56.413∼82.275
			18.718∼23.257
Multiple functions			−0.007∼0.019
			−0.002∼0.006
			−0.0002∼0.0001
			−0.002∼0.001