Research Article

An Evaluation Method of Rock Brittleness Based on the Prepeak Crack Initiation and Postpeak Stress Drop Characteristics

Table 6

Calculation results of each index of granite under different loading modes.

Loading modeBIBi·BiiComparison of brittleness indicesQualitative analysis of the test curve
B1B2B3B4B5

Unloading0.940.570.261.280.671.22Brittleness
Compression0.400.440.130.430.431.08Strain softening