Mechanical Characteristics and Mesostructural Damage of Saturated Limestone under Different Load and Unload Paths

Figure 4

T₂ spectrum distributions for different loading rates and initial peak stresses before and after the test: (a) σ₀ = 2.5 MPa, IA cycling; (b) σ₀ = 2.5 MPa, RIA cycling; (c) σ₀ = 2.5 MPa, DIA cycling; (d)  = 0.2 mm/min, IA cycling; (e)  = 0.2 mm/min, RIA cycling; and (f)  = 0.2 mm/min, DIA cycling.

(a)

(b)

(c)

(d)

(e)

(f)