Study on Mechanism of Cumulative Directional Blasting of Brittle Karst Limestone in the Guizhou Province

Table 4

The brittleness index for different types of rocks.

Rock types	B1	B2	Evaluation
Jinping marble	14.78	293.24	Brittle
Cryptic basalt of Baihetan	10.56	1822.25	Brittle
Almond-shaped basalt	13.92	624.81	Brittle
Project limestone of Taoziya tunnel	22.1	248.76	Brittle