Research Article
Investigation on the Ground Pressure Induced by Hard Roof Fracturing at Different Layers during Extra Thick Coal Seam Mining
Table 4
The calculated elasticity modulus of strain gauges.
| No. | Weight (N) | Strain (10-3) | Elasticity modulus (GPa) |
| 1 | 32 | 210 | 0.121322414 | 64.4 | 412 | 0.124451178 |
| 2 | 32 | 230 | 0.110772639 | 64.4 | 428 | 0.119798798 |
| 3 | 32 | 330 | 0.077205173 | 64.4 | 540 | 0.09495164 |
| 4 | 32 | 290 | 0.087854162 | 64.4 | 690 | 0.074309979 |
| Avg. | | | 0.101333248 |
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