Experimental Study on Dynamic Tensile Mechanical Behavior and Fracture Mechanical Characteristics of Sandstone with a Single Prefabricated Fissure

Table 3

Factors and levels of response variables.

Code value	Code level	Fissure angle, θ (^°)	Strain rate,; (s−^1)
X1	−1	0	104.07
X2	1	90	234.03