Study on the Porosity of Saturated Fragmentized Coals during Creep Process and Constitutive Relation

Table 5

Comparison of correlation coefficients of the Kelvin–Voigt model and the fitting curve of first index decay of fragmentized coals with different grain sizes.

Grain size correlation coefficient	m1	m2	m3	m4	m5
Exponential decay curve fitting	0.99937	0.99549	0.99439	0.99866	0.99835
Kelvin–Voigt creep model	0.99965	0.995799	0.9954751	0.9988852	0.9989241