Characterization and Modeling Study on Softening and Seepage Behavior of Weakly Cemented Sandy Mudstone after Water Injection

Table 1

Mechanical parameters of natural and fully saturated sandy mudstone.

	Confining pressure (MPa)	Deviatoric stress (MPa)	Elasticity modulus (GPa)	Poisson’s ratio /-	Postpeak strain (%)	Cohesion (MPa)	Internal friction angle (°)
Natural sample	0	35.22	3.81	0.20	1.22	7.32	41
	4	44.07	5.19	0.18	1.17
	6	53.80	6.76	0.16	1.10
	8	63.24	8.28	0.17	1.05
Saturated sample	0	15.09	2.75	0.26	1.41	3.24	36
	4	24.12	3.58	0.20	1.37
	6	33.47	4.94	0.17	1.23
	8	45.17	6.18	0.16	1.17