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

Figure 7

Kelvin–Voigt model and the fitting curve of first index decay of fragmentized coals with different grain sizes. (a) m1. (b) m2. (c) m3. (d) m4. (e) m5.

(a)

(b)

(c)

(d)

(e)