Research Article
Research on Hydraulic Fracturing Technology of Long Boreholes along Strata of High Vast Thick Coal Seam
Table 1
Mechanical parameters of coal seam adopted by the model.
| | Type | Coal seam | Type | Coal seam |
| | Degree of uniformity | 6 | Permeability coefficient (md) | 0.1 | | Elastic modulus (MPa) | 1,298 | Void pressure coefficient | 0.4 | | Poisson’s ratio, μ | 0.23 | Compressive strength (MPa) | 6.5 | | Friction angle (degree) | 28 | Coupling coefficient | 0.3 | | Pressed rabi | 10 | Bulk weight (kg/m3) | 1,390 | | Initial porosity of coal seam (%) | 5.84 | Adsorption constant, a (MPa−1) | 29.70 | | Adsorption constant, b (MPa−1) | 0.184 | — | — |
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