Table 1 Main mechanical property parameters of raw coal rock.
From: Hydraulic horizontal slit-stress synergistic unloading fracturing in coal seams
Rock stratum | Density kg/m3 | Elastic modulus/GPa | Tensile strength/MPa | Compressive strength/MPa | Poisson’s ratio |
|---|---|---|---|---|---|
Argillaceous siltstone | 2350 | 18.34 | 1.16 | 13.9 | 0.31 |
No. 9 seam | 1660 | 10.0 | 2.70 | 31.27 | 0.16 |
Argillaceous siltstone | 2730 | 26.4 | 4.23 | 36.6 | 0.20 |
Limestone | 2620 | 34.1 | 7.38 | 46.4 | 0.18 |
Fine sandstone | 2940 | 26.0 | 4.06 | 43.65 | 0.20 |
