Deformation and Strength Characteristics of Structured Clay under Different Stress Paths

Table 3

Stress path test program.

Consolidation confining pressure/kPa	Stress path slope/ɳ	Stress path type	Shear paths	Shear rate	Drainage condition
100/200/300/400/500 (compression path)	3.0	INP	σ 3 = 0, σ1 > 0	0.08 mm/min (strain control)
	∞	KCP	σ 3 < 0, σ1 > 0	0.25 KPa/min (stress control)
	−5.0	DEP	σ 3 < 0, σ1 > 0
	−1.5	DEP	σ 3 < 0, σ1 = 0
	−1.0	DEP	σ 3 < 0, σ1 < 0		Undrained
100/200/300 (tensile path)	1.0	DEP	σ 3 < 0, σ1 < 0	0.25 kPa/min (stress control)
	3.0	DEP	σ 3 = 0, σ1 < 0
	∞	KCP	σ 3 > 0, σ1 < 0
	−5.0	INP	σ 3 > 0, σ1 < 0

Note. INP refers to increasing pressure, KCP denotes keeping constant pressure, and DEP represents decreasing pressure.