Research Article
Uniaxial Compression Creep Relaxation and Grading of Coal Samples via Tests on the Progressive Failure Characteristics
Table 1
Test results for coal samples subjected to uniaxial compression and step relaxation.
| Position | Type | Coal number | /mm | /mm | /kg·m−3 | /m·s−1 | /MPa | /GPa | /GPa | |
| Middle | Conventional uniaxial | MZ1 | 49.4 | 103.7 | 1478 | 1865 | 33.39 | 4.44 | 3.62 | 0.31 | MZ2 | 49.5 | 102.9 | 1482 | 1780 | 19.58 | 4.01 | 2.71 | 0.36 | MZ3 | 49.4 | 100.4 | 1476 | 1770 | 31.97 | 3.95 | 2.93 | 0.26 | Stepwise relaxation | MZ4 | 49.5 | 98.0 | 1437 | 1795 | 26.46 | 4.15 | 3.05 | 0.33 | MZ5 | 49.5 | 99.3 | 1470 | 1770 | 12.10 | 2.40 | 1.53 | 0.21 | MZ6 | 49.5 | 101.1 | 1438 | 1893 | 27.31 | 3.81 | 3.40 | 0.31 |
| Higher stratification | Conventional uniaxial | MS1 | 49.30 | 104.10 | 1470 | 1882 | 15.16 | 3.49 | 2.17 | 0.23 | MS2 | 49.50 | 100.60 | 1479 | 1729 | 15.28 | 3.30 | 1.95 | 0.36 | MS3 | 49.50 | 101.50 | 1461 | 1774 | 17.43 | 3.33 | 1.95 | 0.34 | Stepwise creep | MS4 | 49.70 | 102.40 | 1471 | 1965 | 7.97 | 2.16 | 1.64 | 0.19 | MS5 | 49.50 | 100.90 | 1469 | 1755 | 8.42 | 2.04 | 1.20 | 0.21 | MS6 | 49.50 | 98.20 | 1483 | 1839 | 15.50 | 3.65 | 2.71 | 0.30 |
|
|