Research on the Influence of Mining Height on the Movement Characteristics of Overlying Strata during Extremely Thick Coal Seam Fully Mechanized Sublevel Caving Mining

Table 1

The statistics of top coal, immediate roof, and basic roof caving interval.

Serial number	Press to name	Face advance distance		Roof weighting pace
		4 m mining height (m)	7.5 m mining height (m)	4 m mining height (m)	7.5 m mining height (m)
1	The top coal caved in thick	29.68	22.08	29.68	22.08
2	Direct roof first caving	42.00	23.84	42.00	23.84
3	Primary top pressure	49.04	37.92	49.04	37.92
4	The first period roof weighting	63.12	52.00	14.08	14.08
5	The second period roof weighting	86.00	67.36	22.88	15.36
6	The third period roof weighting	93.04	75.64	7.04	8.28
7	The fourth period roof weighting	110.80	95.76	17.76	20.12
8	The fifth period roof weighting	119.08	106.32	8.27	10.56
9	The sixth period roof weighting	134.56	121.96	15.46	15.64
10	The seventh period roof weighting	145.24	132.20	10.68	10.24
11	The eighth period roof weighting	161.48	140.76	16.25	8.56
12	The ninth period roof weighting	171.16	154.24	9.67	13.48
13	The average of periodic roof weighting pace	—	—	13.57	12.90