Relationship between Brittleness Index and Crack Initiation Stress Ratio for Different Rock Types

Table 3

Summary of mechanical parameters of limestone samples.

No	σci (MPa)	σc (MPa)	σt (MPa)	α	σci/σc	Brittleness index
						B1	B2	B3	B4
S01	46.560	75.600	8.700	5.352	0.616	8.690	0.794	328.860	18.134
S02	37.776	80.100	6.870	5.499	0.472	11.659	0.842	275.144	16.587
S03	54.096	89.300	9.620	5.623	0.606	9.283	0.805	429.533	20.725
S04	40.640	64.400	7.500	5.419	0.631	8.587	0.791	241.500	15.540
S05	33.072	84.600	6.540	5.057	0.391	12.936	0.856	276.642	16.633
S06	32.528	60.800	5.330	6.103	0.535	11.407	0.839	162.032	12.729
S07	56.960	78.700	9.030	6.308	0.724	8.715	0.794	355.331	18.850
S08	47.488	86.200	8.160	5.820	0.551	10.564	0.827	351.696	18.754