Research Article

Stability of Close Chambers Surrounding Rock in Deep and Comprehensive Control Technology

Table 2

Main rock mechanical parameters.

Rock formation nameVolume modulus (GPa)Shear modulus (GPa)Density (kg·m−3)Internal friction angle (°)Bonding force (MPa)Tensile strength (MPa)

Overburden9.02.4250036.02.53.7
Sandstone7.02.5240031.53.73.8
Siltstone7.02.0250031.02.5
Sandstone7.02.5240031.53.73.8
Sandy mudstone6.42.4230032.51.83.5