Variation of Rock Mass Pressure during Tunnel Construction in Phyllite Stratum

Table 4

Fitting correlation coefficient between rock mass pressure and settlement.

Function types	Results	Y0	Y3	Y4	Y5	Y6
Logarithmic function	Correlation coefficient R^2	0.764	0.285	0.370	0.013	0.546
Logistic function	Correlation coefficient R^2	0.946	0.949	0.974	0.064	0.929
Multiple functions	Correlation coefficient R^2	0.941	0.868	0.965	0.619	0.932