A Novel Coal Burst Criterion of Anchored Roadway Surrounding Rock under Dynamic Disturbance

Table 2

Mechanical properties of coal and rock strata in 401102 working face.

Lithology	Density (kg/m^3)	Elastic modulus (GPa)	Uniaxial compressive strength (MPa)	Poisson’s ratio	Cohesion (MPa)	Internal friction angle (°)
Siltstone	2,370	8.7	26.1	0.24	4.2	35
Medium-grained sandstone	2,450	6.3	23.2	0.25	3.8	33
Mudstone	2,260	5.4	18.6	0.28	3.3	32
Number 4 coal seam	1,400	2.0	12.5	0.35	2.0	30
Hard fine sandstone	2,530	10.5	28.4	0.22	4.7	38