Deformation and Failure Mechanism of Roadway Sensitive to Stress Disturbance and Its Zonal Support Technology

Table 3

Physical and mechanical properties of the strata.

Stratum	Density; kg·m^−3	Bulk modulus GPa	Shear modulus Gpa	Friction angle; °	Cohesion; Mpa	Tensile strength; Mpa
Roof	2300	3.3	1.9	23	0.13	0.7
#6 coal seam	1350	2.5	1.45	20	0.15	0.2
Floor	2400	3.6	201	25	0.19	0.8