The Physicomechanical Deterioration Characteristics and Mesoscopic Damage Analysis of Sandstone under Acidic Environment

Table 8

Fitting parameters of relationship between damage variable and peak strength.

Mechanical parameters	Soaking solution	a	b	c	R^2	Soaking solution	a	b	c	R^2
Peak stress (MPa)	pH = 1 H2SO4	97.182	−10.989	3.201	0.998	pH = 1 HCl	99.241	−9.709	1.801	0.998
	pH = 3 H2SO4	80.707	−14.706	5.463	0.999	pH = 3 HCl	160.863	−15.873	4.792	0.994
	pH = 5 H2SO4	251.895	−22.727	6.616	0.994	pH = 5 HCl	101.375	−15.151	5.652	0.999
Peak strain (10^−3)	pH = 1 H2SO4	−136.857	−0.359	133.024	0.999	pH = 1 HCl	−96.811	−0.615	90.179	0.999
	pH = 3 H2SO4	−25.711	−3.484	20.779	0.997	pH = 3 HCl	−30.601	−4.808	18.731	0.994
	pH = 5 H2SO4	−26.029	−6.711	15.758	0.998	pH = 5 HCl	−27.452	−3.802	21.141	0.999
Elastic modulus (GPa)	pH = 1 H2SO4	97.182	−11.001	3.201	0.998	pH = 1 HCl	99.241	−9.709	1.801	0.998
	pH = 3 H2SO4	80.707	−14.706	5.463	0.999	pH = 3 HCl	160.863	−15.873	4.792	0.994
	pH = 5 H2SO4	251.895	−22.727	6.616	0.994	pH = 5 HCl	101.375	−15.151	5.652	0.999