Mechanism of Hydraulic Fracturing Cutting Hard Basic Roof to Prevent Rockburst

Table 1

Main parameters of geological conditions and technical conditions.

Name of parameters	Symbols	Unit	Value
Maximum in situ horizontal stress	σH	MPa	200
Maximum in situ horizontal stress	σh	MPa	215
Vertical in situ stress		MPa	250
Buried depth	H	m	1000
Main roof tensile strength	σt	MPa	2
Poisson’s ratio of the main roof rock mass formation	μ	Dimensionless	0.2
Internal friction angle	φ	°	42
Elasticity modulus	E	GPa	2.58
Stress concentration coefficient	K	Dimensionless	2.5
Average formation volume force	γ	N/m^3	25000
Density of the main roof rock mass	ρ	Kg/m^3	2630