Research Article
Study on the Upper Limit of Roof Failure in Soft Rock Roadway
Table 7
Physical and mechanical parameters of rock strata.
| | Lithologic characters | Bulk modulus (GPa) | Tensile strength (MPa) | Shear modulus (GPa) | Density (kg/m3) | The angle of internal friction (°) | The force of cohesion (MPa) |
| | Coal | 0.23 | 1.25 | 0.33 | 1430 | 25 | 1.20 | | Fine sandstone | 3.56 | 1.57 | 1.80 | 2750 | 35 | 1.30 | | Siltstone | 2.56 | 1.54 | 0.40 | 2770 | 36 | 1.50 | | Oil shale | 0.26 | 0.80 | 1.22 | 2400 | 26 | 0.80 | | Mudstone | 0.16 | 1.00 | 0.15 | 2287 | 31 | 1.00 |
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