Mechanical Properties of High-Temperature Granite under Liquid Nitrogen Cooling

Table 5

The fracture toughness of different samples.

Rock sample name	Fracture toughness (MPa·m^1/2)	Average value (MPa·m^1/2)
25-1 non	2.31	2.06
25-2 non	1.81
25-1	2.46	2.42
25-2	2.38
100-1	2.65	2.37
100-2	2.09
200-1	2.84	2.58
200-2	2.31
300-1	1.29	1.725
300-2	2.16
400-1	1.77	1.295
400-2	0.82