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| Date | Advancing distance (m) | Underground pressure behaviors in working face | Weighting interval (m) |
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| March 15 | 224.1 | The weighting strength was large, the resistance of supports increased obviously, the safety valves of columns opened, the columns sunk 100–200 mm, and the coal rib spalled largely. | |
| March 21 | 267.8 | Weighting strength was normal, supports resistance was not obvious, safety valves of columns opened individually, and the sinking of columns was not obvious. The resistance of 59# and 69# supports increased. | 43.7 |
| March 25 | 285.7 | The pressure of 42–82# supports increased to 34–39 MPa, the spalling of coal rib was 0.5–0.8 m, and the safety valves of columns all opened. The spalling depth of coal rib at 2–14# and 90–104# supports was 0.5–1.0 m. | 17.9 |
| March 30 | 305.0 | The resistance of 35–80# supports increased, the pressure was 35–39 MPa, and most of the safety valves were opened. The spalling depth of 85–91# supports was large, and the top coal at 94–111# supports was broken. | 19.3 |
| April 6 | 348.0 | The front extension beams of 45–47# and 54–60# supports deformed 20 pieces, and 4 pieces of guards were damaged; the dumbbell pins of scraper conveyor at 56-57# supports broke 2 pieces. | 43.0 |
| April 9 | 366.2 | The pressure of 22–100# supports increased to 33–38 MPa. Next day, the top coal leaked at 37-38# and 41–43# supports; the top coal at 5–88# supports was fragmentized, and the height of the roof caving was 1.0–2.5 m. | 18.2 |
| April 16 | 409.5 | Before the weighting, there was a sound of roof collapse in the goaf; 16 safety valves of 57–75# columns were shot out; the rear tail cylinder of 81# support bursts. During the weighting, all tail windshields were blown over. There were 13 columns of supports damaged in total. | 43.4 |
| April 19 | 435.7 | The rear columns of 69# support were posted down, safety valves of 39–100# supports were mostly opened, the roof at 68, 74, 75, 107, and 108# supports were fragmentized, and the coal rib spalled at 13, 14, 58, 59, and 68# supports. | 26.2 |
| April 26 | 486.5 | The weighting first happened at 59# support; safety valves of 49–70# supports opened about 80%; the columns of 57–65# supports could not stretch. | 50.9 |
| May 1 | 520.7 | The safety valves of 0–72# supports were all opened, and the flex volumes of the columns for 53–66# supports were only 20 mm; the average pressure of 16–72# supports were 36 MPa. | 34.2 |
| May 5 | 539.2 | The resistance of 69–99# supports increased, the maximum pressure was 42 MPa, and the average was 38 MPa; the roof at 45–85# supports was broken; the coal rib spalled slightly at 70–80# supports. | 18.6 |
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