FEM Analyses for T-H-M-M Coupling Processes in Dual-Porosity Rock Mass under Stress Corrosion and Pressure Solution

Table 3

Parameters for stress corrosion and pressure solution.

Parameter	Unit	Values
Empirical constant, 𝑎	—	5.0
Origin asperity contact-area ratio, 𝑅𝑐0	—	0.1
Nominal asperity contact-area ratio, 𝑅	—	1.0
Roughness coefficient of fracture, JRC	—	2.5
Factor, 𝐴H2O	ms^−1	1.12×10^−4 T
Factor, 𝐴OH^−	ms^−1	2.51×10^3 T
Origin aperture, 𝐸0	m	0.0125
Residual aperture, 𝐸𝑟	m	0.0025
Constant, 𝑏^∗H2O	N^−1 m^3/2	2.69×10^−5 (quartz)
Constant, 𝑏^∗OH−	N^−1 m^3/2	1.78×10^−5 (quartz)
Activation energy, 𝐸𝑎	J·mol^−1	7.0×10^4 (quartz)
Heat of fusion, 𝐸𝑚	J·mol^−1	8.57×10^3 (quartz)
Activation enthalpy for H2O, Δ𝐻H2O	J·mol^−1	6.6×10^4
Activation enthalpy for OH^−, Δ𝐻OH^−	J·mol^−1	8.27×10^4
Reference dissolution rate constant, 𝑘^0+	mol·m^−2 s^−1	1.59
Infinitesimal distance from crack tip, 𝑟	m	1.0×10^−6
Gas constant, 𝑅	J·mol^−1 K^−1	8.31
Temperature of fusion, 𝑇𝑚	K	1883 (quartz)
Molar volume, 𝑉𝑚	m^3 mol^−1	2.27×10^−5 (quartz)
Fraction of Si–O reacting with H2O, 𝜃^H2OSi−O	—	0.99921 (pH = 7)
Fraction of Si–O reacting with OH^−, 𝜃^OH−Si−O	—	0.00079 (pH = 7)